[riverkid]

Originally Posted by rewboss

Did you mean "prescriptive" here? Descriptive grammar certainly does explain how a language really works: that's its job. Your request for strict, clear-cut hard-and-fast rules sounds more like a request for prescriptive grammar.

"... how a language really works". Where does that leave prescriptive grammar? It explains how language doesn't actually work.

Many prescriptive rules are neither hard and fast nor clear cut. They are simply false. Descriptive grammar provides all that's needed for any student to understand how language works. Think about it; prescription doesn't describe how language works; of what use is something like that?

Originally Posted by rewboss

I think that, at this point, what riverkid and I disagree on is the abstract matter of why native speakers use finished adverbs with the present perfect: he formulates a rule and calls it an "override", while I'm suggesting that native speakers modify their utterances in mid-speech and so produce non-standard structures.

Rewboss, you're making the unwarranted assumption that just because prescriptive grammar failed to note this difference in language use that it's nonstandard. It's a standard gambit for speech. In both examples I gave, there was no midstream change. Both people, Tdol and T Blair rolled right thru with no pause whatsoever.

You also make the unwarranted assumption that this is a cast in stone rule when you really have no idea as to how long this particular use has been in use.

Actually that's the hallmark of prescriptive grammar. In their zeal to provide "rules" there was not enough thought given to how language really works. The result was/is a sorry collection of guidelines; the may/can rule; the restrictive/nonrestrictive nonsense; the you must use the subjunctive form 'were' with if; the sequence of tenses mixup; the dismal analysis of reported speech; ...

Originally Posted by rewboss

On a real practical level, though, it boils down to the same thing: native speakers prefer not to use finished adverbs with the present perfect, but sometimes they do.

It's not really a preference as much as a language/grammatical issue. Native speakers use contractions as a matter of course. Overrides come when they wish to be more strident, serious, when they wish to show anger.

This isn't/is not something that they decide midstream, it's a naturally occurring language gambit. So too with the past time adverb override with the present perfect. The present perfect has its roles but sometimes these can be overridden to express a different nuance.