There was an interview a few days ago with a foreign cyclist who was saying that for the first time in years he is fairly confident the tour is pretty much clean. A big part of his reasoning was that everything Sky do well can be explained by signing top quality talent and lots of little 1% gains. 1% gain on clothing, 1% on helmet, 1% on training, 1% on tactics, 1% on bike. In contrast in the past he has often felt that other riders were a big step ahead of him that could only be explained by drugs.

Other stats (based on rider weight and performace) suggest that the top riders of today are significantly weaker than those of 5, 10, 15 years ago. Given all the other advantages they have now it would seem that 'drug-free' is the most likely explaination for this.

I read another article which took us right back to the start of the British Cycling resurgence and pointed out that it has taken years and years before British Cycling would even enter men's road races - they felt that the british men had to focus on track cycling which is much cleaner - to chuck them into the world of men's pro road cycling would be to risk drugs - it is only as the sport has got cleaner that Sky have moved into that area.

Also note that Sky have refused to sign Millar, and he's only gone into the Olympic team due to a legal challenge.

I am not saying that the TdF is clean, I'm not certain Sky are clean. But I am certain that the Tour is much much cleaner than it has ever been, and that the whole Sky set-up from top to bottom, origins to today, make it more likely Sky are clean than most other teams.