it's a nice move.
It is a demo.
hard to really say how high percentage that move would be vs a skilled opponent.
it seems to work well against the a-typical demonstration attacker.
But consider if he had clinched the old mans head or deflected his hand away and off the push or went for the shot from the 3 point range instead of stepping right into the gate.
Ultimately, it is hard to gauge the value of a technique without having true resistance. But the technique does look simple enough in and of itself and it is obvious that the guy has good foundation. He maintains the ridge pole throughout his entire motion. The attacker doesn't have any effect whatsoever. that's good power even in a demonstration setting.