So why would anyone take on this practice, especially if it's going to take a long time to learn? If you were blown away by the demonstration of "IP", then maybe you are willing to take it on faith alone. Maybe, if you're a very trusting person, taking it on some "authority's" word, maybe enough. But I have been down the "trust me" road before, and I would like to see some proof that there are results at the end of the road.
I feel you in some ways, but what's funny to me is that most "Hard Art" martial artists I know say almost this exact same thing about Aikido in general. Why would anyone do that, it takes so long to learn and who knows if it will ever be effective...