Thanks, good advice. This Spring, that connecting flight thru DEN to ASE, with less than an hour layover, and then the short, free shuttle from ASE to the condo at Snowmass, was extremely convenient. But, so far, no great deals from here to ASE -- and, BTW, ticket prices to HDN from here are off the charts.
Tickets for flights from DC airports to DEN are enough cheaper than tickets for flights thru DEN to ongoing stops (ASE, EGE, HDN) that the savings would pay for the rental car. So the only issue would be time -- whether driving out from DEN on 12/26 or 12/27 and returning back to there on 1/1 or 1/2 would be "off peak".
OTOH, as much as I'd like to get some more skiing in the West, if air ticket prices stay high for the Xmas period, from here in DC we have the fall-back of packing the car, pointing it north, and driving up to Stowe.