I'd say that the best way to size up a manager's tactical ability is to see how he does against different types of teams, how he sets up the team, his lineup and directions to players. I was glad to see Tim mix it up against Swansea, instead of sticking with 2 forwards, and I'd expect his game plan against City to be different from what he put out against Palace, for example.
I'm under no illusions about the strength of our team, relative to City's, but am looking forward to seeing how Tim approaches the match.