I am not sure if it is locally different in America, but "You should have got out of the car when I told you so" sounds much better to me than "You should have gotten ..." This sounds right to me; I get, I got, I have got.
In the Midwest, you'd get a "where'd they go to school?" look if you used "have got" - but most grammar sites I did a quick check of say while "gotten" is correct, "got" is acceptable.
Yes, I know. I just meant that by exploring other words, we are going off topic. 'Got' changed, 'forgot', etc, didn't, so it's irrelevant to this particular argument. But I did have a conversation at work today about it. Someone said 'gotten' was useful because otherwise there is no difference between: I have got a car. (I possess a car--possession) and I have got a car. (I have just gone out and bought one--action/process) However, I was not totally won over, because not many Americans use 'have got', so they would say 'I have a car' for possession. Discriminating between the two meanings is not a problem I have ever come across with Brits. When I googled, most sites seemed of the consensus that 'gotten' is archaic in Britian and has not been used for around 300 years, although it may linger on in a few dialects (although I've never come across that). It exists in North America, particularly New England, because it continued to be used, while it faded out in Britain, so it isn't modern, apparently. Funny how so many American English words are the older form than the forms customary in Britain. Something to do with isolated communities, perhaps?
No, it is the formally recognized past participle of get in every US English dictionary I have checked, with no alternatives. However, "got" and "gotten" are very widely used, and misused, words, so it's not surprising that so many people don't intuitively select the right one by the "sounds right" criterion.
I'm not convinced either. For obtaining a car I would just say "I got a car". Yes -- we both changed things, but we changed different things.
Part of the confusion probably arises because "get" and "have" are verbs with very similar meaning. However, forms of "have" also serve as auxilliary verbs in several English compound verb tenses. However, "have got" appears to be an idiom synonymous with "have". It doesn't analyze grammatically as a recognized compound verb tense, but it is undeniably in widespread use.
Yes, the "I have got" basically says "I have have", whereas "I have gotten" means "I have received" ('received' with all its own nuances )
It does in British English It's a perfectly regular present perfect for us. As discussed, it's never necessary in terms of meaning (it always means either "have" or "got"), but it's also important to remember that language isn't always just about the meaning of the words. The subtext matters too, and "I have" sounds much more formal to me than "I've got". It's the language of a person asserting their status. If somebody says "I have a car" instead of "I've got a car", it sounds to me as if they're not only bridling at the suggestion that they don't have a car, they also resent the suggestion that they're the sort of person who might not have one. "I've got" is much more useful. It's not all about grammar and economy!
And I already discussed that. But in the context given, it was used with simple present tense semantics. As such, it does not parse correctly unless you treat "have got" as idiomatic. Constructs like this confuse the hell out of non-English speakers who are trying to fit sentences to grammar rules. Sometimes you just have to shrug and say, "It's English."