Oliver: I found the answer!
Eureka! The best thing for Aspen traffic is giving buses their own lane all the way to and from Main Street, right? Keep buses in their own lane, and the other lane will flow regular traffic better, too. This is possible with a couple of one-way, two-lane bridges in and out of Aspen.
A one-way, two-lane cut-and-fill bridge through Marolt Ranch taking traffic into town will have a smaller impact through there.
Th existing bridge on Castle Creek can be the improved two-lane bridge driving out of town.
In the future, eventually replace that bridge with another one right next to it. This approach would spread out the funding requirements over a longer period of time.
Turn the old bridge into an affordable spot for locals to eat. I bet there would be a line out the door for the view!
And, God forbid if Aspen ever needs a quick evacuation, but four lanes out of town would be super helpful.
Patrick John Oliver