Here is a wicked head kick KO from Its Showtime fighter Anderson "Braddock" Silva on Freddy Kemayo. Savate does the block he was trying where you drop your left arm and bring your right hand across to shield. Freddy did not tighten up his technique and the angle was off allowing the kick to whiz by with seriously consequences. Personally I think this is a foolish way to cover a round kick to the head, where keeping his left arm high and tight on his head would have protected him better allowing his arm to take the brunt of the force and not his melon!
As always keep your hands up!