The problem I have with the "you have to feel a guy who has it" thing is: A if they are not near you, why would you spend the time and money to track down something that is likely not worth it? And B there is not control with this, what is happening could be some kind of placebo effect.
There must be some tangible proof. Something outside of, this and that guy say, or "I felt it, it is amazing", or 5 years ago so-and-so beat up a professional fighter. Something other then, you just have to feel someone who has it. If nothing else you should be able to film someone "feeling it", and we could see what happened to them when they "felt it".
Chris, I don't really have any answers that I think will satisfy you - I think if there's any opportunity to get to the Mike Sigman seminar in San Fran coming up, you absolutely should go - it's an excellent foot in the door to "this stuff".
On the other hand, I would still stick by the story that "it has to be felt" and "it's different". Because that's been my experience. I grew up playing judo and wrestling, competed in contact karate, did some boxing and have mixed it up with enough people that like to hit/submit that I'm not going to just blow smoke or be hypnotized.
Having said that, there's people that are convinced they are "already doing that" after a seminar on internal strength as well. So, I think people "do" have different experiences. I think between Mike Sigman and Akuzawa getting out in the west coast, those would be the best bets if you didn't want to do a Chen style seminar with one of the bigger names (depending on what's being taught, you might not get to really feel the goods anyways).