what mach. posted looked to me to be a theoretical reason why one shouldn't accept subtypes, and you can't really say that that reason is false by applying practical reasons. You can say that there are practical reasons why one shouldn't use subtypes though-- and I guess it's up to proponents of "subtypes exist" theory to provide practical reasons why they do "exist" or are practically existing.

I for one think that a theory of subtypes might explain my relationships better than the one right now; I may or may not be right about that.

EDIT: oops, didn't see Baby had replied already.