“Playing a 4-2-3-1 system has been unbelievably successful for us, gave us the second-most points in the Championship and one of the most in Europe [since Harris returned as head coach in February]. So why rip it up and start again. But to have options to start or come off the bench, is hugely positive for us. Everything is about profile of players."
You can't argue with that for a reason not to use a 4-4-2 system.
Maybe 4-4-2 is his plan B these days - Something he was criticised for not having in the past.