"Cadel Evans' performances are the best way to measure this. He's been stable for the past eight years. He doesn't do any better than in previous years. It's the Schlecks and Contador who are slower. This Tour has been one of the slowest on the climbs since 2004," commented Grappe, who is usually known for his scepticism with regard to doping.
On stage 19 to l’Alpe d'Huez, where the individual times of each rider were officially clocked, Euskaltel-Euskadi's Samuel Sanchez recorded the best time with 41:45 minutes. But this is only the 24th best time in history. The day's winner Pierre Rolland (Europcar) climbed the mountain in 42:22 - yet in 2006, it took Fränk Schleck 40:46 minutes to get to the top en route to victory, while Floyd Landis and Andreas Klöden were clocked at 38:34 the same day.
Of course, one should always take into account the conditions of the day, the stage length prior to the climb and many other factors that can come into play. Still, the head doctor of the French cycling federation Armand Mégret, was convinced that this year's Tour has been cleaner just from watching the TV images.
from this article on Cyclingnews.com
http://www.cyclingnews.com/news/2011-tour-de-france-the-cleanest-in-recent-years