With the advent of a cleaner peloton eventually someone will win a grand tour clean. Parhaps it was Wiggins. However, what interest's me is the continuing probability of someone winning multiple grand tours clean. From what I am starting to see. A pattern is starting to emerge of possible clean riders having a super high peak perhaps once in a lifetime which can not be regained. Witness Wiggins and Gilbert, and a few others.
Of course with doping this trend of a lifetime peak still existed but it seems less dramatic. A rider could be more consistent from year to year. Look at Contador who is probably riding cleaner now due to the possibility of a lifetime ban. He does not seem to be able to reach the same level of fitness.