I guess I misread the example, sorry. I thought we were talking in the context of inconsistent behavior of Perl as a language and therefore its syntax, but not in the context of an undefined behavior of glob().
We are and we aren't. elektronjunge chose an example that definitely is inconsistent, but I'm not sure that it's really indicative of Perl in general. IMHO, It's a fairly specific kind o broken, where we can't really fix the behavior because of backwards compatibility, but the documentation is just plain inadequate in this case as well.