> although much of Latin grammar survives, much is also lost, plus
> a whole new type of past forms are introduced, those based
> on 'habeo',
This construction exists in Latin. I posted some examples from classical
Latin on this list a while ago. All that happened is that with the change
of pronunciation of /b/ to a fricative, the distinctions in the old system
between, say, amabit and amavit, broke down. So other elements already
present in Latin were used more often - and with ensuing phonetic
developments the new Romance systems emerged. All thoroughly Latin+phonetic
changes. Not a sign of pidgin/creole or anything else, except the normal,
regular, unconditioned, developments within - note the word - within a
language.
Peter