- For Teachers
What seems more important to me is that all native speakers here (and now) think "been" is not the past participle of "go".
If we could produce evidence of BE + to + place used in the past in other tenses than the present perfect, then it would show beyond any shadow of doubt that the assertions of Quirk and the others are wrong.
It's not vitally important - so long as learners use the forms correctly, it doesn't really matter what they believe. I just happen to object very strongly to incorrect 'facts' being presented in discussions of English. I know that been is not ever the past participle of GO. I would like to be able to convince the unbelievers of this.
Them's fightin' words, but I like the cut of your jib!