Carol,
With respect to the desired competitive or examination technique, they are totally identical in every way. Where American style breaks away from Int'l is where the context changes. For example, I would not desire the same technique if I was dancing on a 5x5 social dance floor, even if I was capable of doing it. So being that American style has a variety of possible situations (especially in social dance contexts), I think it's safe to say that there is no single "correct" technique for American style as there is for Int'l style... there is only the technique which works best for the given situation.
I hope this helps answer your question.
Sincerely,
Jonathan Atkinson