Just out of interest Tony D, and you may have answered already earlier (and you are welcome to fib but please don't) - but on a gut feel, what would be your immediate response to this (what I agree is a some what contrived) position?
I actually did give an answer at the end of the bit of mine that you just quoted.
That said, I went back and re-watched the video. He set up the scenario so that the bad guy had his hand practically to the gun, so my original answer about getting between him and the weapon doesn't apply.
I don't think I would gamble on leading off with the kick. With the setup as shown if the kick doesn't do the job completely then there is nothing to stop the bad guy from emptying the gun into me. He doesn't even have to stand up - if he gets the gun and I don't finish him with the kick then he can just roll over on his back and start shooting. Once we reach that point my follow-up options are pretty bad.
I'd probably go with a sort of modified sprawl (easier to demonstrate than to explain in text) with priority on controlling the arm he is reaching with.
Best case scenario: I intercept his arm before he gets the gun and am able to kick the gun away. Then I can control him long enough to do at least stunning damage before disengaging and going for the gun.
Not as good scenario: He grabs the gun, but I am able to control his arm and keep him from aiming it at me. With top control I have a variety of options to make him drop the gun, which I then kick away before working for the finish.
Worst case scenario: He gets the gun and is able to aim and shoot it at me. If the shot isn't immediately fatal, I'm at least in close enough contact that I have a chance of regaining control of the gun and managing a disarm.
Of course, this is all theory. I've never been in this situation and I doubt that a ton of other people have been either. (Of those people who have been in a similar situation, I suspect a majority are law enforcement or military with the option to use their own firearm before the other guy reaches his.)