Canting the gun about half that much does help with controlling the gun when shooting one handed.
Don't know about it being needed two handed.
One drawback to canting the gun is the sights and point of impact will be to the left on the target.
The cant isn't neccessary, but it is supposed to help with the recoil, as well as be more natural of a grip, and this guy even said in an earlier video that he was basing his grip off of other Youtube videos. And, although I am not sure, I am pretty sure that in the high position, based on how the gun hand is across the torso , some of the recoil could be absorbed by the torso if you held the gun arm against yourself. As far as your comment about the sights and POM being to the left of the target, the eye opposite to the shooting hand is the one you sight with, so you will still be able to use the sights and get the result you should expect, especially at the ranges this is meant to be used at, around 1-10 yds.
Why does everyone ridicule CAR? It's not like Weaver, Isoceles, and Chapman are all perfect, the Car system does too, but the biggest one, the lack of really good long range accuracy, can easily be overcome through plenty of training. And without that one thing really in the way, getting past it makes the system inherently superior to traditional stances, IMO.
And above all else, this was just asking if anyone had tried it, not if you thought it was stupid or idiotic or any other negative adjective you can think of. And I bet the one who I quoted, based on the way he worded his post, has not even tried it.