Re: Aikido vs....
Yes, there are some that disagree with his training methods, but they've been effective for him, and while I believe "aliveness" is necessary, without repetition at some point in your training, the precision of technique suffers. Matt Thornton and Roy Harris disagree strongly on this point.
Michael Jen has NEVER competed in a BJJ or submission grappling tournament. He did do a few Judo competitions as a brown belt in BJJ, though, when he was working out with the San Jose State Judo team.
I'm glad you like his instructionals, though. People like different instructionals for different reasons. Some like concepts, some like to be entertained, some like to see as many different techniques for their dollar as they can. For some reason, most of Mike Jen's videos remind me of a private lesson with Joe Moreira. Joe is an encylopedia of techniques!