diff --git a/src/OpenFOAM/matrices/schemes/schemesLookup.C b/src/OpenFOAM/matrices/schemes/schemesLookup.C
index 1695b23b62..c9a1b02865 100644
--- a/src/OpenFOAM/matrices/schemes/schemesLookup.C
+++ b/src/OpenFOAM/matrices/schemes/schemesLookup.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2015 OpenFOAM Foundation
-    Copyright (C) 2019-2022 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -102,6 +102,19 @@ void Foam::schemesLookup::read(const dictionary& dict)
 }
 
 
+const Foam::dictionary& Foam::schemesLookup::selectedDict() const
+{
+    word select;
+
+    if (readIfPresent("select", select, keyType::LITERAL))
+    {
+        return subDict(select);
+    }
+
+    return *this;
+}
+
+
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 Foam::schemesLookup::schemesLookup
@@ -136,7 +149,7 @@ Foam::schemesLookup::schemesLookup
     snGradSchemes_("snGradSchemes", objectPath()),
     laplacianSchemes_("laplacianSchemes", objectPath()),
 
-    fluxRequired_(objectPath() + ".fluxRequired"),
+    fluxRequired_(objectPath() / "fluxRequired"),
     fluxRequiredDefault_(false),
     steady_(false)
 {
@@ -153,7 +166,7 @@ Foam::schemesLookup::schemesLookup
 
     if (readOpt() == IOobject::MUST_READ_IF_MODIFIED)
     {
-        read(schemesDict());
+        read(selectedDict());
     }
 }
 
@@ -177,7 +190,7 @@ bool Foam::schemesLookup::read()
     {
         clear();  // Clear current settings except fluxRequired
 
-        read(schemesDict());
+        read(selectedDict());
 
         return true;
     }
@@ -186,68 +199,58 @@ bool Foam::schemesLookup::read()
 }
 
 
-const Foam::dictionary& Foam::schemesLookup::schemesDict() const
-{
-    if (found("select"))
-    {
-        return subDict(word(lookup("select")));
-    }
-    return *this;
-}
-
-
 Foam::ITstream& Foam::schemesLookup::ddtScheme(const word& name) const
 {
-    DebugInfo<< "Lookup ddtScheme for " << name << endl;
+    DebugInfo<< "Lookup ddt scheme for " << name << endl;
     return ddtSchemes_.lookup(name);
 }
 
 
 Foam::ITstream& Foam::schemesLookup::d2dt2Scheme(const word& name) const
 {
-    DebugInfo<< "Lookup d2dt2Scheme for " << name << endl;
+    DebugInfo<< "Lookup d2dt2 scheme for " << name << endl;
     return d2dt2Schemes_.lookup(name);
 }
 
 
 Foam::ITstream& Foam::schemesLookup::interpolationScheme(const word& name) const
 {
-    DebugInfo<< "Lookup interpolationScheme for " << name << endl;
+    DebugInfo<< "Lookup interpolation scheme for " << name << endl;
     return interpSchemes_.lookup(name);
 }
 
 
 Foam::ITstream& Foam::schemesLookup::divScheme(const word& name) const
 {
-    DebugInfo<< "Lookup divScheme for " << name << endl;
+    DebugInfo<< "Lookup div scheme for " << name << endl;
     return divSchemes_.lookup(name);
 }
 
 
 Foam::ITstream& Foam::schemesLookup::gradScheme(const word& name) const
 {
-    DebugInfo<< "Lookup gradScheme for " << name << endl;
+    DebugInfo<< "Lookup grad scheme for " << name << endl;
     return gradSchemes_.lookup(name);
 }
 
 
 Foam::ITstream& Foam::schemesLookup::lnGradScheme(const word& name) const
 {
-    DebugInfo<< "Lookup lnGradScheme for " << name << endl;
+    DebugInfo<< "Lookup lnGrad scheme for " << name << endl;
     return lnGradSchemes_.lookup(name);
 }
 
 
 Foam::ITstream& Foam::schemesLookup::snGradScheme(const word& name) const
 {
-    DebugInfo<< "Lookup snGradScheme for " << name << endl;
+    DebugInfo<< "Lookup snGrad scheme for " << name << endl;
     return snGradSchemes_.lookup(name);
 }
 
 
 Foam::ITstream& Foam::schemesLookup::laplacianScheme(const word& name) const
 {
-    DebugInfo<< "Lookup laplacianScheme for " << name << endl;
+    DebugInfo<< "Lookup laplacian scheme for " << name << endl;
     return laplacianSchemes_.lookup(name);
 }
 
@@ -266,6 +269,12 @@ bool Foam::schemesLookup::fluxRequired(const word& name) const
 }
 
 
+const Foam::dictionary& Foam::schemesLookup::schemesDict() const
+{
+    return selectedDict();
+}
+
+
 void Foam::schemesLookup::writeDicts(Ostream& os) const
 {
     ddtSchemes_.writeEntryOptional(os);
diff --git a/src/OpenFOAM/matrices/schemes/schemesLookup.H b/src/OpenFOAM/matrices/schemes/schemesLookup.H
index 68473daea5..357dbc1070 100644
--- a/src/OpenFOAM/matrices/schemes/schemesLookup.H
+++ b/src/OpenFOAM/matrices/schemes/schemesLookup.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2015 OpenFOAM Foundation
-    Copyright (C) 2020-2022 OpenCFD Ltd.
+    Copyright (C) 2020-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -30,10 +30,29 @@ Class
 Description
     Selector class for finite area/finite volume differencing schemes.
 
-    The schemes data are treated as MUST_READ_IF_MODIFIED even if
-    the requested readOption is nominally MUST_READ or READ_IF_PRESENT.
-    This allows run-time modifications to behave as expected.
+    The file will contain these types of entries:
+    \table
+      Name         | Description                        | Type | Reqd | Default
+      ddtSchemes   | ddt                                | dict | no   | none
+      d2dt2Schemes | d2dt2 (currently only finite-area) | dict | no   | none
+      interpolationSchemes | interpolation              | dict | no   | linear
+      divSchemes   | div                                | dict | yes  | -
+      gradSchemes  | grad                               | dict | yes  | -
+      lnGradSchemes | line-normal grad (finite-area)    | dict | no | corrected
+      snGradSchemes | surface-normal grad               | dict | no | corrected
+      laplacianSchemes | laplacian                      | dict | yes  | -
+      fluxRequired |                                    | dict | no | -
+    \endtable
 
+    \par select
+    This is a rarely used feature to select between different groups of
+    settings within the file. If unspecified, the file contents are used
+    directly.
+
+Note
+    The schemes data are treated as \c READ_MODIFIED even if the
+    requested \p readOption is nominally MUST_READ or READ_IF_PRESENT.
+    This allows run-time modifications to behave as expected. <br>
     The optional fallback dictionary content for constructors is used
     when a file is missing or for a NO_READ, with a null pointer being
     treated like an empty dictionary.
@@ -154,6 +173,12 @@ class schemesLookup
         //- Read settings from the dictionary
         void read(const dictionary& dict);
 
+        //- The entire dictionary or the optional "select" sub-dictionary.
+        const dictionary& selectedDict() const;
+
+
+    // Generated Methods
+
         //- No copy construct
         schemesLookup(const schemesLookup&) = delete;
 
@@ -190,21 +215,15 @@ public:
 
     // Member Functions
 
-        //- The current schemes dictionary, respects the "select" keyword
+        //- True if default ddt scheme is steady-state
+        bool steady() const noexcept { return steady_; }
+
+        //- True if default ddt scheme is not steady-state
+        bool transient() const noexcept { return !steady_; }
+
+        //- The entire dictionary or the optional "select" sub-dictionary.
         const dictionary& schemesDict() const;
 
-        //- True if default ddtScheme is steady-state
-        bool steady() const noexcept
-        {
-            return steady_;
-        }
-
-        //- True if default ddtScheme is not steady-state
-        bool transient() const noexcept
-        {
-            return !steady_;
-        }
-
 
     // Lookup Access
 
@@ -232,10 +251,10 @@ public:
         //- Get laplacian scheme for given name, or default
         ITstream& laplacianScheme(const word& name) const;
 
-        //- Get flux-required for given name, or default
+        //- Set flux-required for given name (mutable)
         void setFluxRequired(const word& name) const;
 
-        //- Set flux-required for given name (mutable)
+        //- Get flux-required for given name, or default
         bool fluxRequired(const word& name) const;
 
 
@@ -289,7 +308,7 @@ public:
             return laplacianSchemes_.dict_;
         }
 
-        //- Access to flux required dictionary
+        //- Access flux-required dictionary
         const dictionary& fluxRequired() const noexcept
         {
             return fluxRequired_;
@@ -346,7 +365,7 @@ public:
             return laplacianSchemes_.dict_;
         }
 
-        //- Access to flux required dictionary
+        //- Access flux-required dictionary
         dictionary& fluxRequired() noexcept
         {
             return fluxRequired_;
diff --git a/src/OpenFOAM/matrices/schemes/schemesLookupDetail.C b/src/OpenFOAM/matrices/schemes/schemesLookupDetail.C
index 1358ec6402..95a0d47356 100644
--- a/src/OpenFOAM/matrices/schemes/schemesLookupDetail.C
+++ b/src/OpenFOAM/matrices/schemes/schemesLookupDetail.C
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2021 OpenCFD Ltd.
+    Copyright (C) 2021-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -50,9 +50,9 @@ Foam::schemesLookup::lookupDetail::lookupDetail
     }
     else
     {
-        dict_.name() = parentDictPath + "." + name_;
+        dict_.name() = fileName::concat(parentDictPath, name_, '/');
     }
-    default_.name() = dict_.name() + ".default";
+    default_.name() = fileName::concat(dict_.name(), "default", '/');
 }
 
 
diff --git a/src/OpenFOAM/matrices/solution/solution.C b/src/OpenFOAM/matrices/solution/solution.C
index cad46df74c..6e1a92bf48 100644
--- a/src/OpenFOAM/matrices/solution/solution.C
+++ b/src/OpenFOAM/matrices/solution/solution.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2019-2022 OpenCFD Ltd.
+    Copyright (C) 2019-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -41,7 +41,8 @@ namespace Foam
 // List of sub-dictionaries to rewrite
 static const Foam::List<Foam::word> subDictNames
 ({
-    "preconditioner", "smoother"
+    "preconditioner",
+    "smoother"
 });
 
 
@@ -142,6 +143,19 @@ void Foam::solution::read(const dictionary& dict)
 }
 
 
+const Foam::dictionary& Foam::solution::selectedDict() const
+{
+    word select;
+
+    if (readIfPresent("select", select, keyType::LITERAL))
+    {
+        return subDict(select);
+    }
+
+    return *this;
+}
+
+
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 Foam::solution::solution
@@ -183,7 +197,7 @@ Foam::solution::solution
 
     if (readOpt() == IOobject::MUST_READ_IF_MODIFIED)
     {
-        read(solutionDict());
+        read(selectedDict());
     }
 }
 
@@ -201,7 +215,7 @@ Foam::solution::solution
 
 // * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
 
-// A non-default destructor since we had incomplete types in the header
+// No default destructor in header (incomplete types)
 Foam::solution::~solution()
 {}
 
@@ -283,6 +297,17 @@ bool Foam::solution::cache(const word& name) const
 }
 
 
+// void Foam::solution::enableCache(const word& name) const
+// {
+//     if (!cache_.found(name))
+//     {
+//         DebugInfo<< "Cache: enable cache for " << name << endl;
+//         cache_.add(name, true);
+//         caching_ = true;
+//     }
+// }
+
+
 bool Foam::solution::relaxField(const word& name) const
 {
     DebugInfo
@@ -358,12 +383,20 @@ Foam::scalar Foam::solution::equationRelaxationFactor(const word& name) const
 
 const Foam::dictionary& Foam::solution::solutionDict() const
 {
-    if (found("select"))
-    {
-        return subDict(get<word>("select"));
-    }
+    return selectedDict();
+}
 
-    return *this;
+
+const Foam::dictionary& Foam::solution::solutionDict(const word& name) const
+{
+    DebugInfo<< "Lookup subDict : " << name << endl;
+    return selectedDict().subDict(name);
+}
+
+
+const Foam::dictionary& Foam::solution::solversDict() const
+{
+    return solvers_;
 }
 
 
@@ -385,7 +418,7 @@ bool Foam::solution::read()
 {
     if (regIOobject::read())
     {
-        read(solutionDict());
+        read(selectedDict());
 
         return true;
     }
diff --git a/src/OpenFOAM/matrices/solution/solution.H b/src/OpenFOAM/matrices/solution/solution.H
index 65730fb8fb..5c32d227f7 100644
--- a/src/OpenFOAM/matrices/solution/solution.H
+++ b/src/OpenFOAM/matrices/solution/solution.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2020-2022 OpenCFD Ltd.
+    Copyright (C) 2020-2023 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -30,10 +30,43 @@ Class
 Description
     Selector class for relaxation factors, solver type and solution.
 
-    The solution data are treated as MUST_READ_IF_MODIFIED even if
-    the requested readOption is nominally MUST_READ or READ_IF_PRESENT.
-    This allows run-time modifications to behave as expected.
+    The file will contain these types of entries:
 
+    \par solvers { }
+    A sub-dictionary listing of linear solver settings. For example,
+    \verbatim
+    solvers
+    {
+        p
+        {
+            solver          PCG;
+            preconditioner  DIC;
+            tolerance       1e-06;
+            relTol          0.05;
+        }
+    }
+    \endverbatim
+
+    \par select
+    This is a rarely used feature to select between different groups of
+    settings within the file. If unspecified, the file contents are used
+    directly.
+
+    There are currently no other specified entries, but the file will
+    often also contain other solution specifications. For example,
+    \verbatim
+    PIMPLE
+    {
+        nOuterCorrectors 2;
+        nCorrectors     1;
+        nNonOrthogonalCorrectors 0;
+    }
+    \endverbatim
+
+Note
+    The solution data are treated as \c READ_MODIFIED even if the
+    requested \p readOption is nominally MUST_READ or READ_IF_PRESENT.
+    This allows run-time modifications to behave as expected. <br>
     The optional fallback dictionary content for constructors is used
     when a file is missing or for a NO_READ, with a null pointer being
     treated like an empty dictionary.
@@ -100,6 +133,12 @@ class solution
         //- Read settings from the dictionary
         void read(const dictionary&);
 
+        //- The entire dictionary or the optional "select" sub-dictionary.
+        const dictionary& selectedDict() const;
+
+
+    // Generated Methods
+
         //- No copy construct
         solution(const solution&) = delete;
 
@@ -114,7 +153,7 @@ public:
     //  Returns the number of settings changed
     static label upgradeSolverDict(dictionary& dict, const bool verbose=true);
 
-    //- Debug switch
+    //- Debug switch (registered name: "solution")
     static int debug;
 
 
@@ -139,56 +178,64 @@ public:
         );
 
 
-    //- Destructor
+    //- Destructor. Non-default in header (incomplete types)
     virtual ~solution();
 
 
     // Member Functions
 
-        // Access
+    // Access
 
-            //- Return true if the given field should be cached
-            bool cache(const word& name) const;
+        //- True if the given field should be cached
+        bool cache(const word& name) const;
 
-            //- Return true if the relaxation factor is given for the field
-            bool relaxField(const word& name) const;
+        //- True if the relaxation factor is given for the field
+        bool relaxField(const word& name) const;
 
-            //- Return true if the relaxation factor is given for the equation
-            bool relaxEquation(const word& name) const;
+        //- True if the relaxation factor is given for the equation
+        bool relaxEquation(const word& name) const;
 
-            //- Return the relaxation factor for the given field
-            scalar fieldRelaxationFactor(const word& name) const;
+        //- The relaxation factor for the given field
+        scalar fieldRelaxationFactor(const word& name) const;
 
-            //- Return the relaxation factor for the given equation
-            scalar equationRelaxationFactor(const word& name) const;
+        //- The relaxation factor for the given equation
+        scalar equationRelaxationFactor(const word& name) const;
 
-            //- Return the selected sub-dictionary of solvers if the "select"
-            //- keyword is given, otherwise return the complete dictionary
-            const dictionary& solutionDict() const;
+        //- The entire dictionary or the optional "select" sub-dictionary.
+        const dictionary& solutionDict() const;
 
-            //- Return the solver controls dictionary for the given field
-            const dictionary& solverDict(const word& name) const;
+        //- Return \p name sub-dictionary within the solutionDict().
+        //  Same as \c solutionDict().subDict(...)
+        const dictionary& solutionDict(const word& name) const;
 
-            //- Return the solver controls dictionary for the given field
-            const dictionary& solver(const word& name) const;
+        //- The solver controls dictionary (all fields)
+        const dictionary& solversDict() const;
+
+        //- The solver controls dictionary for the given field.
+        //- Same as \c solversDict().subDict(...)
+        const dictionary& solverDict(const word& name) const;
+
+        //- The solver controls dictionary for the given field.
+        //- Same as solverDict(...)
+        const dictionary& solver(const word& name) const;
 
 
-        // Read
+    // Read
 
-            //- Read the solution dictionary
-            bool read();
+        //- Read the solution dictionary
+        bool read();
 
 
-        // Other
+    // Other
 
-            //- Helper for printing cache message
-            template<class FieldType>
-            static void cachePrintMessage
-            (
-                const char* message,
-                const word& name,
-                const FieldType& vf
-            );
+        //- Helper for printing cache message
+        template<class FieldType>
+        static void cachePrintMessage
+        (
+            const char* message,
+            const word& name,
+            const FieldType& fld
+        );
 };
 
 
diff --git a/src/OpenFOAM/matrices/solution/solutionTemplates.C b/src/OpenFOAM/matrices/solution/solutionTemplates.C
index 4a72e9c669..0450b27f10 100644
--- a/src/OpenFOAM/matrices/solution/solutionTemplates.C
+++ b/src/OpenFOAM/matrices/solution/solutionTemplates.C
@@ -34,15 +34,14 @@ void Foam::solution::cachePrintMessage
 (
     const char* message,
     const word& name,
-    const FieldType& vf
+    const FieldType& fld  // == regIOobject
 )
 {
-    if (solution::debug)
+    if (Foam::solution::debug)
     {
-        Info<< "Cache: " << message << token::SPACE << name
-            << ", originating from " << vf.name()
-            << " event No. " << vf.eventNo()
-            << endl;
+        Info<< "Cache: " << message << ' ' << name
+            << ", originating from " << fld.name()
+            << " event:" << fld.eventNo() << endl;
     }
 }