I'd like to welcome you aboard, too. Some of my animus towards prescriptivists was not really aimed at you, though I did use some of your examples.

My point about the dictionary as an authority is that besides only being as good as the lexicographer(s) who put it together, many contain—as you point out—usages and meanings that prescriptivists rail against. (That is modern dictionaries are becoming more descriptivist than prescriptivist.) So, it comes down to some kind of personal choice on the part of he who prescribes. (And, I'm sure any true prescriptivists won't be upset with my using the third person singular masculine personal pronoun to refer to a person of undetermined gender.)

What I was trying to say yesterday is that many of the prescriptivists rules have nothing to do with grammar, and many go against the grain (or spirit or drift) of English. They were invented for all the wrong reasons: split infinitives, for example.

Spelling and punctuation are in need of some sort of overhaulage, but I doubt that would ever happen short of a science fiction scenario of near nuclear devastation. Punctuation especially, as handled by the "experts" (cf. Lynne Truss whose recent book is riddled with mistakes) is a confused and ever changing hodge-podge of "rules".

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Ya got me, too. What's it mean? I teach classes at university, and I must say, in the worst writing examples, even of non-native speakers, I've never ever seen a sentence approaching this kind of incomprehnsibility. That's what I was on about with my reference to accomodation theory. Many folks cannot write formal English, and so they transcribe how they talk, sort of. And, many of their problems, I wouldn't list under grammar, but rather rhetoric and logic.