The south end of JAC is notoriously slippery at times during winter months. The passenger shot video out the left side of the AC never caught sight of a spoiler during the landing roll. On AA's RB211 engined fleet, if all systems are functioning as designed, the reverser sleeve will not translate aft in flight which would allow blocker doors to swivel into position to block fan air. Throttles must be at idle and separate levers mounted low on the front of the throttles must be grasped and raised by a pilot. The copilot was said by the NTSB to have been the PF. He would have been wrestling with the reverse levers. The captain would/should have a ready hand to deploy the ground spoilers if they not auto-deploy simultaneously with touchdown.