[Tallguy]

It was so effective as an institution it almost always won despite the command being handed out to politicians rather than professional soldiers.

That was more or less true of all ancient armies this side of Phillip II of Macedon & his more famous son, Alexander the Great.

Roman forces would have been handled tactically by long-serving professional centurions.

Also, ancient armies were pretty much a one-shot affair. Once a legate released a unit into combat the only move that he had left was to release his reserves, if he had any. A decision that was probably also influenced by his "first spear" centurion.

[Sherman Logan]

True enough. I guess handing supreme command out by accident of birth is even less rational than giving it to the winner of corrupt elections.

There were other supremely talented ancient military leaders, obviously, such as Hannibal, Africanus and Caesar, but their rise to command was in all cases at least as much the result of political factors as of military effectiveness.

OTOH, military talent was also a fast track to political success.