'Johnny G' balk call

[Illini_Ref]

While I agree that it is two separate movements, why is it usually allowed for LHP. I see no rule that defferentiates between right and left handers.

Federation rules say that if you fail to deliver to the plate after starting a motion habitually used in your motion then it is a balk. So then shouldn't the "hanging" of the right leg for a LHP be a balk also???