I bought the book Modern Coin Magic by J.B. Bobo and it's great, but I have a question that the book has not answered so far: ¿Is it good to learn the movements with both hands? ¿Does the right hand (or the master hand) always make palms and difficult movements? In card magic, you always do the movements with the same hands and there is no need or advantage to know how to make the movement with small hands (except when the cards are palmed) As I am new to coin magic, I still do not know if it's not a good or bad thing.
I actually have a slightly different view...
It does hurt to waste time in learning sleights which will never be used by you. In that time, one could have learnt a new way of presenting some effect, improving some effect.
Instead of learning new sleights, and well...many magicians these days do so...they keep on learning the most difficult of sleights and at the end of the day, they have no idea where to use them. And even if they do, they have not developed showmanship or performance persona. So are they magicians? Are they not mere sleight-of-hand artists?
The sole reason for learning a sleight must be:-
a) performing an effect
b) improving the same
So, based on the same logic I say that the only reason for learning a sleight with both hands must be the two above reasons (not a RULE, just my opinion).
I have heard of people having different 'dominant' hands and different 'magic' hands. Meaning, they might be right-handed, but while doing magic, they become left-handed, or vice versa (more common). This approach is completely fine!
Are you asking if small hands are a disadvantage in coin magic?
Because, till now, I have not encountered a sleight like that. However, size of coins MAY be a problem.
Not really actually...
Limitations are self-created and self-destroyed.