Fair comment. As Ryan said, it's a bit of a bikeshed issue. I prefer
"generic", on the basis that I'd prefer to keep the simple name for the
simple use - something as complex as the RuleDispatch version could use
the name "dispatch" (if they want to keep it the name simple) or
"multimethod" (to emphasize that it dispatches on more than just one
argument).

If the consensus is for keeping it as "simplegeneric", I'll go with
that, but I'll wait for other views first.

BTW, another option is simply to clarify the limitations in the
documentation. I can add something there if that would be enough for you.