I'm thinking that Denver to Albuquerque and Tucson were also Shuttle routes at the "peak" (there's an oxymoron if there ever was one). I agree that Reno wasn't Shuttle since DEN-RNO was/is often served by a 757, especially the last flight of the day DEN-RNO and the first RNO-DEN.

Anyone care to find an old timetable and look for those 2XXX-series flights?

BTW, loved the free upgrades DEN-LAS. Definitely a fun flight when the party spirit is flowing, say on a Friday night.