What does he do with his elbow before tip-ball contact? What does he do with his elbow after the ball is gone?
What do you do with your elbow and when relative to tip-ball contact?
The point isn't "when" he drops his elbow.. It's that he drops his elbow.
There are those that advocate (and teach) a pendulum stroke because it supposedly can do anything an elbow drop can, but does not have all the downsides of potential pre-contact elbow drop, but I don't see many world champions using it.