Where did you guys ever get the idea that descriptivists don't believe there are any rules? We describe the language and derive the rules from the language as it is actually used, rather than starting with a set of rules that may have described the language at some time in the nostalgic past and attempting to apply those rules.

Right now I'm looking for the prescripitivist rules that would suggest that one of those sentences listed above is better than any of the others and, hopefully, a citation to some recognized authority acceptable to many, if not all, prescriptivists.

As for the particular use of periods, commas, capitalization, and sentence order in the quoted sentences, they were taken directly, by means of cut-and-paste, from another board where the question has been asked and, to my mind, unsuccessfully answered.