I didn't watch that video but just looking at the image IMO that serves no purpose in hunting situations. Some of the best practice you can do for hunting with a recurve is called stump shooting. All that is is getting a bunch of arrows (blunt tips preferred) and take a walk through the woods picking out targets at varying ranges and shooting at them. Rotten stumps, grass clumps, mushrooms, anything sort of soft. This give your brain valuable information on judging distance and improves your hand/eye coordination with your bow. And if you do it with a buddy its a lot of fun.
As an afterthought I found my best anchor point is my middle finger in the corner of my mouth, bow at approx a 45* cant. I also don't put a "death grip" on my bow but hold it only with my thumb and index finger with the remaining fingers curled up. That works for me.