I believe you can tell if a performer has serious chops when they can knock it out of the park while performing acoustic and singing a Capella.Here's a good example.
--It's a video of RANDY HOUSER doing a raw version of "Boots On" during his USO trip to Iraq earlier this year. (--That's Kellie Pickler and Jamey Johnson on stage with him, but they weren't performing on this song.)