It's true. If you can see Osterland explaining a mentalism effect, whatch it. Not only do you get to
see a great presentation and explanation, but you have many years of performance experience behind
it.
Things that seem ballsy turn out to be normal and acceptable to your audience, while
some simple stuff you may be tempted to let slide by can ruin your show. Even if you do this trick,
you'll appreciate the teach.