The way I see it (for now): a wrestler has a list of moves to use. Each move has power and difficulty ratings. When a grapple is initiated, it goes into a motion comic view of a general lockup. As soon as the wrestlers lock/touch, each player hits the action button. The player who hits the action button closest to when the wrestlers lock/touch gains the advantage.
You can see in the example: P1 has hit their action button 0.5 seconds after the lock/touch happens and P2 has hit their action button 0.3 seconds after the lock/touch happens. That means P2 has the advantage. In this example, P2 has an advantage of 0.2 seconds.
What does that mean? I don't know. Does 0.2 seconds convert to points? How does that relate to the difficulty rating of a move? Just because you win the lockup doesn't mean you can initiate a finisher off the bat.
Perhaps the difficulty rating equates to the number of successful grapples a wrestler has already performed, thus unlocking more grapples available to use. So after two successful grapples, a wrestler is than able to execute from a list of difficulty 0, 1, and 2 grapples. Maybe the advantage gives you room to execute a lower level grapple with room for error. Let's say the 0.2 seconds converts to 2 points, then you can be 0.2 seconds slower than your opponent, but still win the advantage if you're trying to execute a difficulty 0 grapple. This does, however, assume a lower difficulty level grapple has a higher advantage, probably due to its speed to execute?
In terms of the beats and "acts" in a wrestling match, this system doesn't encourage the ups and downs we're used to seeing. It just promotes stronger and stronger moves, an escalation without any rubber banding (i.e. a large leads stays a large lead). That makes for no comebacks and that makes for uninteresting playing. Hmm.