I always tend to use the "Down Palm" to make coins appear from ears. At least that's how i think the palm is called, i havent read about it in many years.
I found that rubbing the index/middle finger and thumb togheter act well as cover to get close from someone eyes. Specially because you can show your hand open just before with your fingers wide appart from each other.
As for the back palm i never got it right so i never used it really, i stayed with the gosh pinch and somekind of reversed french drop where the coin fall in back clip between index and middle finger. This one is probably in bobo's book ill see if i can grab the name when i come back from work.
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Edited: Its not in bobo's book and i have no clue where it come from or how its called, this is bothering me much!
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Roth has excellent technic i believe that is what your studying right now (MCM) so im not worry for your coin work!
