Hmm. I treat these terms differently than you are using them here.
Generally, military usage would break things out in three levels like this:
- tactical level (small)
- operational level (middle)
- strategic level (big)
The tactical level is basically the nitty gritty of direct combat with the enemy, face to face, unit to unit, regiments against regiments, brigades against brigades, etc.
The operational level is above the tactical level and contains it. This is more about the movements that get you into tactical combat with the enemy. Generally, this is about moving larger units, often both in-contact with the enemy and out-of-contact with the enemy.
The strategic level is above the operational level and includes it. This is very high-level maneuvering and decision-making.
There are of course gradients within all that and actions that can be spread across more than one.
Sherman was very good at the operational and strategic levels. He was not-so-good at the tactical level. He was good at the defensive side of tactical situations because he became more determined and grim when he was attacked and things narrowed to simple decisions. On the tactical offensive (when he attacked other people) he was mediocre-to-just-plain-bad (see Chickasaw Bluffs, Chattanooga, the Atlanta Campaign, anything up to and including Bentonville). He avoided getting into these situations in 1864-5, avoided large set-piece battles, and concentrated on doing what he did well (the operational and strategic level).
Grant was much better on the tactical offensive than Sherman was, if only because he was willing to close with the enemy and fight him. Sherman wanted to avoid that, IMHO because he did not believe he was good at it.