Regarding this post, which continues to get a lot of reader interest, I haven't yet provided my own take on who has the better chance at a fast finish at Leadville--the fast guy or the mountain dude. But now I'm ready to offer my take.
I see myself more as the guy whose weekly approach is to run 100 miles in 13 hours versus 100 miles in 18 hours. That's partially a product of the environment in which I live (Parker, Colorado, which has limited dirt trails and is 40 minutes from the mountains) but also of my identity as a runner. When it comes to races, I'm a runner, not a hiker (though I love recreational hiking). I do like the occasional difficult mountain race, such as the Jemez 50-Mile (which involves some insanely steep, scree-laced climbs and descents), but by and large I'm attracted to races that involve a lot of running, not hiking. That's not to minimize races that involve a lot of hiking; I consider Hardrock to be the ultimate challenge and one day I will confront that gnarly course as an official entrant.
What I most like about Leadville is that it gives me everything I want in a race at this stage in my life--mountains, beautiful trails and a little bit of road. My favorite section of Leadville is when you're dropping into Twin Lakes on the outbound. This part of the Colorado Trail is awesomely runnable and you can just fly into Twin Lakes.
Getting back to who has the better approach--the fast guy or the mountain guy--I think that for Leadville the faster guy's training is, by its nature, higher-risk/higher-reward than the mountain guy's. Because he did his intervals, tempo runs, etc. and has good turnover and efficiency, the fast guy stands the chance of running a stout time at Leadville since it's a "runner's race." But, if things go bad for him, which is very possible in a high-altitude environment like Leadville, he may have a hard time getting into the finish since he didn't put in a lot of time on his feet like the mountain guy.
Conversely, the mountain guy, even though his speed and efficiency aren't as good as the fast guy's, has put in the time on his feet to be able to withstand lots of punishment and a long day out there on the Leadville course. His training approach, while quite taxing from a time standpoint, has built up tremendous strength that will benefit him on Hope Pass as well as late in the race. His approach is lower-risk, but I'm not sure if it's higher-reward or lower-reward since he probably wouldn't stand a chance if the fast guy is having a good day.
At Leadville, I give the slight nod to the fast guy. Only slight, though.
In a race like Hardrock, I go with the mountain guy ten times out of ten.
I believe to my marrow that if you want to be a better runner, yes, you have to hit some good volume and go really long on a regular basis. If you're doing a race like Leadville, you'd better get out there on the mountain trails and do some serious climbing and descending. But you also need to log good quality. Go to the track and challenge yourself with some fast intervals that will improve your VO2 max and efficiency. Do a weekly tempo run, which will enhance your strength and lactate threshold, allowing you to go harder for longer. If you do no quality and just emphasis long, slow distance, you're not going to get faster.
Ultimately, I think the optimal training program is to marry both approaches and get to the mountain trails while also spending time at the track and on the road doing fast stuff. If you can do both, you're in a good place.
Where am I right? Where am I wrong?