Johnson is probably the best aerially in the squad, I can see the thinking behind it. I don’t think either he or Keith make the calls on who marks whom.
Agree on the midfield, and it’s been our Achilles heel all season long. The one consistent positive is Mount’s runs and his creativity, but that’s not balanced with someone who can control the tempo. Will Hughes is the player you describe; two years on and I’m angrier about that sale than ever before.
Our defence would look totally different with that kind of midfield in front of it. The full backs were providing more movement for the CBs than any of the midfield 5, no surprise they often look exposed.