I was tempted to answer the same as above, but thankfully I waited enough XD
I re-read, and saw you made a mistake in the opening post, you mentionned "ring" and "middle". But whatever.
I kind of tried and my index and middle are shaking a little (though my hands are kind of usually "shaky" when their fingers are closed with strength, regardless of which are closed).
In what way your hand can't stay still? '-'
Maybe that's because Yamada's way to close those two fingers is just unusual (at least to me), when I think about it once again.
