I've had a few spectators who, during various tricks (especially something like ambitious card) demand to have each step varified, ie

Me - "Lets put your card into the middle of the deck" (puts card halfway into deck)

Spectator - "Let me see if thats really my card" (bends down to try and look at card)

If you shy away or refuse to let them look, then it just confirms their suspicion that this may not be the same card. I'm pretty sure it has nothing to do with my performance. I keep things fast moving and exciting. I think it has to do with those individual spectators.
Anyway, how do you handle these type of spectators who ask you to "prove" what you're doing at each step. (Let me see the other hand, can I see the top card etc etc etc)??

cheers

Laugh it off, finish the effect and then stop performing for them because their are weird.

There's a technique for the ACR that allows you to show the card that you're putting into the middle is their card even though it's still on the top of the deck. It's taught on the Million Dollar Card Magic DVD, which is a great DVD to get if you aren't a beginner to card magic.

I ALWAYS use this technique because specs invariably want to see that it's their card at some point, so it's a great tool to have in your ACR arsenal.

Hm. Depending on where you preform, if you are just have people lean down and look at the card, then what you do is you get lower then there point. Street magicians often do that they feel safer that way because no one in there right mind will put there face to the ground and try to look at the card. If they do laugh excitingly, and slap your hands down on your knee... pushing the card into the deck then ask, " What are you doing!? " they will stop. Then if they say, " Trying to see my card. " or which ever " trying to see the card you put in the deck"

Oh! well here, " reveal it on top of the deck. "

Or do the long distant spinner. " I am sure I put your card back into the deck but maybe if I can get the right gust... THERE! " then fire the card off catch it and give it to them

I'm not sure if it's what you're talking about but I use a sleight called Topper. Is this what you mean?

Craig