People with jutting jaws are more likely to have open throats and hence be less susceptible to snoring and sleep apnoea. Chris Worsnop points out that superheroes such as Superman and Batman are often drawn with strong jutting jaws, a feature which, since the time we lived in caves, has been seen as attractive to women. The reason women may be attracted to jutting jaws may have nothing to do with jutting biceps or jutting anything else; it simply makes it less likely they will have to put up with snoring.
A woman needed half her leg amputated after she slipped and broke the leg as she was cleaning her bath while she was still asleep. Not even the pain of a broken bone woke her and the angle at which she fell cut off circulation to the leg, killing the limb. When she finally awoke, she was close to multi-organ collapse.