In his announcement, Volkmar Felsch writes:
Before it is returned, the resulting presentation is being simplified
by appropriate calls of the function 'SimplifyPresentation', but without
allowing it to eliminate any generators.
How do you do this? That is exactly what I need.
Also, the manual says that it may be useful to apply SimplifyPresentation
more than once. What is a good rule of thumb for the number of times to
apply SimplifyPresentation to a presentation? Does this rule change if
no generator is being eliminated at any stage?
Thanks for your help.