Nice video.
Did anyone count how many times he swept the cameraman? LOL
What I teach is very much the same, with three important differences:
1. Plant the fingertips of your support hand in between the on-grip fingers of the shooting hand, just below the knuckes of the shooting hand.
2. Then, wrap the support hand around the grip and to the rear. This does not require much force (your hands don'e get tired so quickly) and you will notice as wrapping back around the grip, it forces firmer contact of the fingers of the shooting hand into the grip frontstrap, and the "fleshy" part of the supprot hand covers the exposed part of the grip. This ensures more bone-on-grip contact front-to-back on the grip, without overly straining the hands.
3. With weapon in hand, grip set firmly, lock wrists, elbows and shoulders (applies to isoceles and weaver/modified weaver), and with shooting hand side push outwards towards target from the shoulder (imagine punching someone with a fist, the entire arm is locked and pushing outwards); with the support hand, pull in from the hand. This push-pull action stabilizes the gun, helps control recoil, and aids is readdressing the target for follow-up shots.
Additionally, if using a Weaver or Modified Weaver, this action helps comfortably and consistently to raise the shoulder of the shooting hand, allowing shooter to sight along the length of the arm towards the front sight and thus the target. For rapid follow-up shots, you are basically aiming with your arm, not your front sight.
Shoot safe!