Anyone catch the Ryan Hall / Gray Maynard fight?
Hall is a leg lock expert. His strategy is to pepper his opponent with front leg kicks, and when his opponent closes the distance, Hall tries to roll into a leg lock position.
It's an effective strategy partly because you're not allowed to kick a downed opponent.
So, he can go to the ground intentionally and if he gets his position, attempt to tear up his opponent's knee without having to worry about getting kneed or kicked in the head.
The rule should be that if you intentionally go to the ground, your head is fair game to be kicked.