DIRE CONSEQUENSES: Head outside single leg can result in the defender grabbing a guillotine and jumping backwards breaking the attacker's neck! This is why you DO NOT do head OUTSIDE for single leg.
Don't try techniques you don't fully understand - especially takedowns
Scissor takedown is often a cause of terrible leg injuries that is initiated when someone is defending a singleleg takedown
Rib injury if you turn one way and body lock is facing another.
Shoot, they catch a guillotine and fall on your head