...And here's proof!
Vince edited this video of a CMD class we recently had, the whole time we just did really light "MMA" sparring. No elbows or knees, but kicks, takedowns and grappling were allowed. I'm the fellow with the dark blue t-shirt (also designed by Vince), the black Fairtex shorts and the light blue gloves.
I found it tremendously fun, though pretty draining. As you may guess from the sloppy takedown, much of the video was shot close to the end of class. I think I did alright as far as endurance is concerned, and I have only Vince's conditioning classes to thank for it. If you're looking to train for MMA or even standup, I'd really recommend some kind of interval training regime, the benefits to be had are simply immense.
I had loads of fun integrating BJJ into my sparring. I can't get enough of it as is, so any opportunity to throw in some grappling is always cool. It was really interesting to again take note of how much the dynamics of "normal" BJJ training shift when not only do you not have a gi to slow things down, but someone is also trying to punch you in the face.