I'm looking forward to this race this year. With Lance showing up to contest the race in much better condition. He seems to be the favorite this year. But I have a few observations.
It seems unlikely that Wiens would have the time to put into training since he is basically a retired and working ex-bike racer. Lance has been training 5-7 hours a day probably 6 days a week for the last year. And it is rumored that Lance is planning to bring a lot of fast roadies with him to try and set a really fast pace. They want to do the race in around 6 hours which will be cutting 45 minutes off from the fastest course record.
This seems unrealistic to me since most fit racers finish in 7-10 hours. But Wiens says that it is possible since the first 45 miles is usually ridden at a moderate pace before the big hills start.
One thing that I think Wiens has an advantage with is that even though he has probably not had the same amount of time to train, he has spend more of his time on dirt trails on a 22-24 pound mountain bike. I have to wonder how much of a difference this makes when you see that Lances training has been pretty much all on the road on a 15-16 pound road bike. Although, I'm sure Lance will have at least 2-3 weeks of mountain bike training before the race. How much time off he took after the TDF would be interesting to know. I'm sure that he took at least three days off doing nothing. Then maybe three or four more days doing light spinning for an hour or two.
Another thing to consider for Wiens is the nature of mountain bike training. In off road riding there is more variation of tempo, seat position, wattage output, cadence, etc. Modern sports science has found that this kind of varied training effect has a greater potential to create high levels of fitness because the body adapts so fast to the same routine. Of course, this is why even the pro roadies do different kinds of pedaling cadences and tempos. But I have to think that in the end, putting in the same amount of time on the mountain bike would bring greater levels of fitness. So more can be accomplished in less time.