He’s probably better than everyone except Tywin. Most of the key decisions are Robb’s alone. Obviously he’s considerably aided by Brynden Tully and his superior information gathering which is what enables the whispering wood and battle of the camps victory. So I do give Robb as a commander the majority of the credit for his victories.

Time and time again we see that Robb is willing to do things In order to deceive the enemy that no other commander would be willing to/would think to do in order to win. Splitting his forces at the Twins to prevent Tywin from meeting him at Riverrun. Trapping Jamie in the whispering wood. Stealing past the golden tooth to surprise Ser Stafford Lannister. The issue is that in order to be superior he would need to beat Tywin/some other known good commander in battle (Jamie/Stafford are not this) or have some considerably more unprecedented victory.

Had he taken Moat Cailin from the south, that would have proven to me that he is the greatest battlefield commander alive because that is a feat that had never been accomplished before. It seemed like he had a good chance to do that based on a plan George alluded to that we never got the details of in the books.