A side shot at a deer's head is somewhat risky and I won't do it. A frontal shot, if low will go right through the neck. Same with a shot from the rear. It is not impossible to hit ONLY the jaw with a face on shot (Nothing is impossible with deer and bullets), but the risk of a bad shot is no worse than anywhere else you shoot.

I never noticed more blood from a head shot. I know some guys that soak the meat in salt water overnight if it looks too bloody. I do it with small game and it works. The salt draws the blood out into the water.