Screw those. Get this.
You are definitely safe. You neck is protected from slashing. Yes, your wind-pipe is also protected from the frontal assault. In addition, you can use the helmet as your weapon as head-butting is pretty much lethal (those are steel cages).
Just kidding.
I think the dangerous hits are to the top of your head and the behind your head. (Unless of course you hit so hard to bruise the inside.) Some of bicycle helmets have very lean protection to the back and I feel that's not good. Is this right?
T