Short answer , Yes! They never actually fought as their doctrine was intially written, that is massed mobile force, but they proved themselves beyond all doubt. The M10's acted as tank destroyers, self proppelled artillery , and assualt artillery.
Though never specifically trained for any of these supplementary roles, the intial training of the men, similar to Ranger or Commando training allowed them to adapt , improvise and overcome. When they crews had no vehicles, their training made them invaluable as scouts, FOO and just plain highly trained infantary.
Recommended reading: The Tank Killers by Harry Yeide