He's got the right idea. It works. But it's tougher than that to unlock a really good lockdown though. And in the second comp video he doesn't clear the leg completely anyway; the guy still has his heel in there digging on the calf muscle (which hurts) and leaving the door open to reestablish the lockdown.
If you lift your leg and get underneath the heel, now you can unhook it and follow the same process to hide your leg from your opponent.