That's a pretty big statement to make...
I've rolled with BJJ blacks over here that've never felt this stuff before. Maybe Pete can chime in on his experiences (who trained with the a4Mbar g0d Rickson Gracie himself back in the day?
Whoops, just saw this. I trained with Rickson for a significant amount of time back in the day, rolled with Royce, Royler, Rorion, Rigan Machado, etc. While I'm dropping names, I've also trained with Dan Inosanto, Paul Vunak, Pendekar Paul DeThouars, and felt the other three DeThouars brothers, Burton Richardson, William Cheung and other Wing Chun people, some scary Thai boxers (there's a reliable style), and lots of other people more obscure in name but not in ability from a variety of styles. Oh yes, and Aikido too.
With all those names you'd think I have some ability, but it just goes to show what name dropping is good for.
But I've been around and seen quite a bit over the years. When I saw Mike talking about internal stuff I asked some questions, and from written description it didn't sound like anything unusual or different, but I filed it away for reference. Then when the opportunity to see Mike came about, I went and saw for myself. Surprise! Like everybody else, it was different than what I expected, and completely different from any other art or practitioner I'd encountered.
So, this is the norm. You think you know, but there's a very good chance you don't, and anyone who is a card-carrying martial artist without a bias against finding out he hasn't seen it all will go check for himself. There are more than enough experienced straight shooters that have gone to see Mike, Dan, etc. and posted here about it that this shouldn't be a serious issue anymore for anyone who bothers to check the archives.