We were playing cannon fodder garbage in those games and everyone was buzzing because Mourinho was gone, when reality set in the 4-4-2 diamond became the clear formation to get the best out of our strikers regardless of who is playing, it even got Lukaku back in a lot of fans good graces. Just look at Saturday, we started out with a 4-3-3 trying to play up to Rashford, he got knocked over or dispossessed nearly every time, we changed to the diamond with Mata in behind and had our best spell of the game, as Marcus could then play as the type of striker he actually is and not trying to be one he isn't.
I didn't ignore it, I've been saying for ages we need a top RB regardless of formation, and Shaw has started to offer more in attack in recent weeks, something Ole said they'd been working on. If we get the fullbacks going and a top class false 9/#10 in then the diamond will work well, it already works for us reasonably well despite missing 3 key pieces. The 4-3-3 isn't going to have any sustainability for us unless we buy another striker and return Rashford to the LW to compete with Martial. This whole Martial/Rashford/Sancho videogame idea is never going to work IMO, the pieces are ill fitting.