SchoutenAllowZeroGain is an option for
FCSchoutenBruteForce and other functions that attempt to
simplify the input expression by applying Schouten’s identity. When set
to True, the algorithm would apply Schouten’s identity to
the given expression even if this does not decrease the total number of
terms in the expression. This is sometimes useful when the algorithm
gets stuck and cannot find further transformation that would make the
expression shorter.
Overview, FCSchoutenBruteForce.