The average speed of this year’s Tour was 39.883 kph (that’s almost 25 mph), which made it faster than the Tours of the past two years, and faster than eight of the 10 Tours held when there was no drugs test for EPO (1991 to 2000). To average that speed (including long mountain stages when speeds average closer to 30 kph than 40 kph), you can only imagine what it’s like to hold a wheel in a peloton often moving at between 50 and 60 kph. That’s no sinecure, and only the fittest, most talented athletes are capable of doing this day after day.
[Incredible, when you think about the mountain stages.]
turnings :: daniel berlinger 
But comparably, how was the course? Can you look at total elevation across the years?
I can’t (well not easily) but it’s probably in the same neighborhood over the last twenty years. Interesting that in the “doping” years the Tour was slower on avg. than now. Everyone argued the opposite just a few years ago, that the bunch was “supercharged”. SO either it’s not cleaner and the dope is better, or the entire theory about how much performance elevation anyone attains is wrong, or the entire thing is so complex that no single input will vastly change the results except in the smallest sample.