This seems pretty uncomfortable for me-
1) I'm not very athletic. I have trouble walking down the street without tripping over nothing.
2) I'm undersized in length (not a problem you have @Rod Hagen) I have enough problems staying inside a nice booty without trying to extend one of my legs to grind someone's face into the mattress
3) Maybe it's one of those things you have to experience the doing of, but even if I were endowed more, it just seems awkward and uncomfortable. Wouldn't it be easier to use your hand to force someone's head into the mattress?
Gman
To me it sounds quite sexy. Personally, I couldn't do it as I would be afraid to sprain something and at my age I stay away from activities that could result in any type of sprain (e.g. back, neck, tongue, etc.).