I think just about every piano text I've ever seen has exercises devoted to getting the thumb around, thumb under, thumb over etc. etc. There are a zillion of them. I'd like to do some thumb exercises for a total of a few minutes a week.Are there some that are most widely considered excellent (by people who believe in the value of exercises)? Or all they all more or less the same?
I don't play the piano. But I seem to recall that Brahms has some good exercises for the thumb.