The 'old' explanation used to be, 'It's all done with mirrors!' backed with the occasional, 'He's using a trap door!' which is very strange if you're doing a card trick! We've seen the programmes featuring 'that geezer' where the specs have hysterics at an effect then try to come up with a rational explanation such as, ' Are you a guru? You must be a guru'.
However, this kind of comment really ought to be taken as a compliment despite what Derren Brown says - I'm ploughing through the same book and there's a lot of deep and serious thinking involved there but life will be different for each of us so don't be disappointed if reality is occasionally different.
I've used these comments to advantage on several occasions - if they think you're using mirrors and a trap door then tell them they're quite right and swiftly lead on to Dice Thru' Mirror (refer to
http://www.emagictricks.co.uk/product_i ... ts_id=3333 for details) where you clearly show them a trap door and two mirrors.
Perhaps this would be an ideal opportunity to share some typical spec reactions and the sort of (clean!) responses we make - or would like to have made? This might help others when they encounter similar reactions.
How did you do that? = Very well indeed!
How did you do that? = If I told you that I'd have to kill you!
Can you do the one like David Blaine does? = No, we have an agreement - he doesn't do mine and I don't do his.
Can you do the one like David Blaine does? = No but I can do it without freezing my ass off in blocks of ice!
Can you do the one that Tommy Cooper used to do? = No, nobody can do anything like Tommy used to do!
I know how that's done! = OK, here's the cards/ropes/props/whatever, give it a go!
You're cheating! = Yes - I'm supposed to!
OK folks, add away!