I think you could very well be right. Charlo's power and physicality could be an issue, but I think Plant's speed and boxing ability would ultimately be the deciding factors.
I'm starting to doubt Jermall here since he has really been leaning hard on the size advantage. On the other hand, perhaps not draining himself to 160 could unlock some improvements in other areas.
I think you have some people confused here. Your thread title says Jarmell, but your opening post says Jarmall. Just a heads up. Some folks bringing up the Harrison fight.
When I consider Plant's attributes, I don't usually think "great timing." I do, however, think his hand and foot speed will trouble Charlo. Timing, hand speed, boxing acumen....whatever, we both seem to be in agreement that Plant decisions Charlo.
I've seen the fight more than once. And like I said, Plant was the faster (of hand and foot), more fluid fighter, particularly in the first half of the fight when he was most effective. His timing was of secondary importance.