I've had a bit of a good-spirited running debate with some of my buddies over which specific mountaineering objective would be harder. Car to car solo of Disappointment Cleaver on Rainier, or car to car solo of all three Tetons (Grand, Middle, South) via Owen Spalding on the Grand then the north ridge of the Middle? Here's the backstory: I have lots of Teton mountaineering experience and they have lots of Rainier and Pacific Northwest experience, which has produced our (obvious) biases. I have never climbed Rainier, they have never climbed in the Tetons.
So, here are the stats:
Rainier via Disappointment Cleaver:
Peak Elevation 14410
Elevation Gain: 9000+
Mileage Round Trip: 18+
Primary Technical Challenge: glacier travel, crevasses
Peak Elevation: 13,770
Elevation Gain: 10,300+
Mileage Round Trip: 19+
Primary Technical Challenge: low grade (5.5-5.6) technical rock climbing and big exposure
Obviously, comparing these is a little bit of an apples and oranges situation, since each is very different from the other. On paper, they're fairly similar. The Tetons have the edge in total elevation gain and mileage, but Rainier wins in elevation above sea level, and probably presents more weather-related challenges.
I'm talking about taking everything into effect: physical endurance, requisite skill, mental toughness, overall exposure to total cumulative hazards etc... All that being said... Which is would be more difficult? Personally, I say the Teton traverse, but I've never climbed Rainier. Obviously, they claim Rainier, but we both agree that it's a close race. Remember, either must be done in a single calendar day.