In my defense of Sherman, I stuck with moral issues. However, it’s worth noting that influential early armored warfare theorist Basil Liddell Hart wrote glowingly of what he called Sherman’s “indirect approach.” During his march to the sea and the subsequent march through the Carolinas, Sherman repeatedly positioned his column to threaten more than one point. The Confederates often split their already inadequate forces to defend every target, and sometimes he ignored all the obvious targets and moved past them to seize a different objective, generally leading the enemy to evacuate the bypassed areas without a fight. Liddell Hart regarded it as masterful maneuver warfare in the tradition of Sun Tzu, baffling and unbalancing your enemies.
His principal opponent, Joseph E. Johnston, at first was comforted by the opinion of Confederate military engineers that the flooded rivers lying across his path in the Carolinas would completely halt military operations. But upon learning that Sherman was crossing the swamps and rivers at a dozen miles a day, corduroying roads and building bridges as he came, Johnston admitted “…there has been no such army in existence since the days of Julius Caesar.”
Lastly, remember at the time Sherman departed for his march to the sea, it was widely believed he could not survive logistically so far from safe railheads, and Confederate cavalry would isolate and starve his army to death. Grant almost didn’t allow him to try. It was a daring feat.
It’s also true that Sherman’s march worked, strategically – if you read Confederate diaries and newspaper accounts, Sherman’s penetrations (and the inability of the rebel armies to oppose him) thoroughly disheartened Confederates and led many of them to see the end was indeed near.
Anyway, my candidates for elimination:
McClellan: 2
Pretty much a sure thing; not only did he manage to turn stalemates into defeats, he is possibly the most cautious commander on this list, ruled by his fears on too many occasions. And failing to capitalize on Special Order 191 is almost uniquely incompetent if one strives to be considered a great military mind.
Kesselring: 2
Probably a decent general. But a baboon could have held the spine of Italy against longitudinal advance – it was the best place in Europe for the Allies to invade, from the German point of view.
Tito: 1
Masterfully husbanded his forces to be certain he dominated postwar Yugoslavia. Masterfully rooted out disloyalty and informers.
Mediocre strategist in terms of irregular warfare.
Fortunately, he was able to capitalize when the Red Army’s advance doomed his German occupiers.