at about 13.20 in the video you reset the rig after testing it. i was just wandering what button that was?
Technically I'm "clearing all transforms" to reset to pose position. You can accomplish this by first being in Pose Mode, then selecting all bones with CTRL + A, and finally clearing transforms with ALT + G (clears translation), ALT + R (clears rotation), ALT +S (clears scale). And I just quickly run through those 3 commands in that order.