So what do I do about that weak hand thumb?

I know the saying goes something like "shooters shouldn't have thumbs", but seriously. When I shoot my Glock or my 1911, I don't have issues with the weapon cycling and my thumb doesn't catch anything even though it sort of "rests" against the left side of the slide (right handed shooter).

I suspect this is not ideal though. Is the general idea to curl it downward? Or perhaps just flag it out with the whole "flying thumbs" idea. I shot a Beretta 92 the other day and the thumb pressure was causing a FTE about every 2nd round.

Thanks in advance.

Are you referring to two-handed or SHO/WHO work? I think it's the latter, but it's hard to tell for certain from reading your post.

plenty of disagreement about where the thimb(s) should go. Some say thumbs forward is best, some say thumbs curled down is best, some run thumbs straight up. Personaly I do thumbs forward for two-hands auto shooting, thumbs down for two-hand revolver, and thumb down for SHO and WHO shooting.

I don't think it matters as long as you stay away from the possible issues with the thumb:

Don't exert lateral pressure into the frame (unless you do it deliberately to counter the force of the trigger pull - couple different ways to go on this point.)

Don't interfere with controls on the gun.

Don't interfere with the trigger finger.

Don't position the thumb so that it interferes with maximum skin-to-gun contact or grip pressure.

Don't vary thumb position/pressure as you are shooting (causes grip variation across a string of fire.)

The overriding theme here is to get the thumb out of the way of everything else.

My strong hand thumb is curled down and locked on the grip. My weak hand thumb is locked over it.