Yet, weirdly are no-one's primary rival.
Forest and Derby have each other, Coventry historically see Villa as their main rivals. So, 3 derbys, but not the major focus of any of them.
Have you ever been in a dressing room? They may be in theory grown men, in practice they are single minded over grown adolescents with more money then sense and egos to match. Match that with various different little sub groups and cliques, all with the slightly different behavioural trends.
I stand by the comparison.
You see it in the classroom. A disciplinarian would just be ridiculed by children now, it becomes a game to get a reaction and run rings around them.
Maintaining high standards whilst building positive relationships is a big challenge, often seemingly opposing in aim.... But not impossible. RM clearly couldn't maintain high standards of approach in the areas that needed discipline even if he could (and it was his clear strength) get the players on side.