Roman commanders underestimated?

[machinor]

Didn't usual Roman battle strategy more or less consist of steamrolling the enemy army with the infantry mass? IIRC it was that strategy that Hannibal exploited in the Cannae.

Also, one has to keep in mind, that most of the higher rank served in the army only for a relatively short term. So the real veterans were the soldiers and lower rank officers like the centurions. A wise commander would rely on them and their experience instead of his own dubious military knowledge.
After all, there is a reason, a military commander would be pronounced 'Imperator' by the legion and not by the senat or the generals.