I'm pretty happy with this effect. There's really nothing new here, but the routine is pretty clean
and well-constructed.
My only complaint is that the explanation is not very clear. There
are places in which he refers to the "top" of the envelope or the "back" of the envelope, and I
could swear he's got it backwards... or perhaps if you're holding the flap towards you, there's some
confusion as to "top" and "bottom". Some photos would've made things a lot clearer... even better,
a 5 minute performance video would've been great. I don't enjoy trying to follow convoluted
writing, but since the effect is a good one, it's worth the effort.
