message: Give recommendation and reasoning for new printing behavior.
diff: @@ -120,7 +120,7 @@ protected:
  /** @name Convergence
  */
  ///@{
  - int max_iter; //< Iteration threshold
  + int max_iter; //< Limit for the number of iterations the solver is allowed to do
  double rel_tol; //< Convergence criterion: $ ||r|| <= rel_{tol}*||r_0|| $
  double abs_tol; //< Convergence criterion: $ ||r|| <= abs_{tol} $
  ///@}
  @@ -155,8 +155,8 @@ public:
  ///@}
  /** @ingroup Report
  - Directly set the behavior on which information will be printed to ::mfem::out.
  - The behavior for the print level for all iterative solvers is
  + Old way to directly set the behavior on which information will be printed
  + to ::mfem::out. The behavior for the print level for all iterative solvers is
  -1: Suppress all outputs
  0: Print information about all detected issues (e.g. no convergence)
  1: Same as level 0, but with detailed information about each iteration
  @@ -164,12 +164,20 @@ public:
  >2: Custom print options which are dependent on the specific solver
  In the MPI build just the rank 0 node produces outputs.
  +
  + @note It is recommended to use SetPrintLevel(PrintOptions) over this method.
  + If additional custom printing options are required for a derived iterative
  + solver a new SetPrintLevel(PrintOptions) with a custom PrintOptions struct
  + can be defined.
  */
  virtual void SetPrintLevel(int print_lvl);
  /** @ingroup Report
  Sets the information reporting behavior in a backwards compatible way.
  In the MPI build just the rank 0 node produces outputs.
  +
  + @note It is recommended to define new PrintOption structs if more custom
  + print levels should be supported for a subclass.
  */
  void SetPrintLevel(PrintOptions);
  