It is not possible to more fully expose and present a rear end than when in this position. When one is told to bend over and grab their ankles, one is, in effect, being told, 'we intend to thoroughly paddle your bottom. So not only will you present your rear-end but you will stretch and endeavor to stick it up and out as far as you absolutely positively can. Since the angle between the legs and the upper body is well under 90 degrees, this position spreads the cheeks and exposes the rectum and genitals more than any other position. Inflexible people can't reach their ankles without bending their knees.
Men run the risk of getting their testicles whacked.
Non-fleshy butts get pulled tightly across the pelvic bones and don't provide enough padding when a heavy paddle is used. Depending on the person, I think this position can be more visually appealing because the back can be arched a bit which perks up the bottom. In fact, the further up the legs the hands are placed, the more the spankee can arch their back and stick out their rump. Again, feet should be shoulder width apart and hand positioning enforced. Because the back can be arched and bottom upturned, it should be required, both prior and during the paddling.