Hall and Zahid wrestle so similarly against top tier guys, waiting for the counter rather than getting to legs. Both guys are so good getting behind that getting stuffed on a shot is often fatal, and since both guys are otherwise waiting to counter, one go-behind can win the match. And as good as Hall's go-behinds are, Zahid has a reach advantage that makes his a little better.
I suspect the best way to take Zahid down is to get to both his legs at the same time, but Hall isn't really known for having a blast double. Still, I imagine the coaches have worked with Hall on how to beat Zahid since Zahid is Hall's only real competition at the weight. But does Hall show his hand now? I'm not sure I would. Maybe wrestle the same match you keep wrestling against him now and save the new approach for March.
I don't think the coaches approach things this way, with so much emphasis on the process instead of results, but you only need to watch Hall and Zahid's two most recent matches to know that they're playing chess. They know each other as well as two opponents do in large part because they're similar.