Nit-man,
Yes, we looked at 10 or 12 players (among them Mizerak and Sigel), and all of them did not drop until noticeably and obviously after impact.
One problem many elbow droppers have is during a crucial moment in games the stroke gets tighter and the grip hand moves forward a bit, so that the arm is now dropping before contact, decreasing to some degree the precision of their stroke (though certainly they can still make some balls).
Hey, maybe Dr. Dave will take a look at this issue with his high speed camera - I would trust those results.
i don't know how much stock i put into this elbow drop stuff. it's nothing for SVB or Donnie mills to follow through and whip the cue ball around the table. shorter guys don't have as much arm to produce the long cueing action that seems to go hand in hand with that sort of cb reaction