A lot of "gamers" shoot with their support wrist canted forward drastically like that. I'm not using that term disparagingly either; they shoot really really good and faster than I do. My experience is that this stance requires the arms be almost completely straight and locked at the elbow.
For a while there I flirted with shooting like that when I was hot for USPSA matches. But as I moved away from that and started thinking about practical shooting and human biomechanics, my grip has evolved so that my elbows stay somewhat bent, my head isn't so low into the sight picture but rather the gun further up to my eye-level, and my hands almost in a pugilistic configuration wrapped around the gun.
It's still a thumbs forward style, but my wrist isn't cammed forward as far as yours is and I find that it gives me more maneuverability and stability for shooting on the move.