I am usually no fan either, but I think he's tried other things before and this is the final chance. Not long ago he said, some players need to be protected by not playing them.
Since you told the poster twice that he's wrong, let me tell you that you are wrong, too. Junk food would definitely be a problem, even if he trains like a maniac and isn't overweight. Nutrition is just as important as physical exercise to a professional football player. Your body works a lot less efficiently, if you just eat garbage. It affects your sleep, which then affects your recovery and your performances. Consuming too much sugar would cause a lack of concentration, which is also very important for a professional. There are various upsides to eating healthy for an athlete.
Baba Rahman is having a tough time with his old coach at Schalke as well. Filipe Luis couldn't replace Azpilicueta, who has been one of the best defenders in the league. During that season Ivanovic was playing very well, so there was no need to change Azpilicueta's position. Obviously you could ask, why they bought Filipe Luis in the fist place, but during that season, considering the back four was very consistent in terms of performances and game time, they pretty much played with Ivanovic - Terry - Cahill - Azpilicueta most of the time and it worked.
You've got to wonder, what we are doing, when we are trying to sign a player. I really hope Mourinho changes our approach there. Asking youth coaches about his attitude is not the most difficult thing to do and we should be looking at how players respond to pressure and stress.
Difference here is that Pogba is probably with Ibrahimovic and Mata the fittest player in our squad.
Edit: And Valencia obviously.