Yeah...I think we need to abandon 3atb to be honest. I respect Poch saying it isn't about systems when the players aren't fighting and there is some truth to that, but I think 3atb was great when we were trying to get all of Dier, Toby, Jan, Wanyama and Dembele into the team. And it was great when 3atb was a formation that we were one of the first to use regularly after Chelsea and get that advantage. Now even a laggard like Wenger is using it, Toby is out, Dier hasn't proved he can be a leader at the back and keeps losing concentration, and Wanyama's absence leaves a gaping hole in our midfield.
Back to 4-2-3-1, or 4-3-3 with Dier holding, Son on one wing alongside Kane and fitting the other players around that, could work. Poch always seemed to spot solutions ahead of time, be an innovator and be comfortable taking a risk. 3atb has lost the advantage it once gave us I think, for a bunch of reasons.