“What exactly is “grand tactical” supposed to be anyways?”
I associate the term with Napoleonic warfare more than more modern warfare. It means something between ‘operational’ and ‘strategic’ levels of control and planning in armies. It is concerned with shaping the battle by manoeuvre before combat begins, executing the battle plan and the decisions made immediately after the battle is concluded. It falls just short of planning and commanding the whole campaign. That is my interpretation at least.
Cheers and good gaming.