OK Gross city. listen to this. This is related by a former teammate in "Tour" magazine so I believe it.

Jan Ullrich in the TdF (don't remember what year) - the day of L'Alpe d'Huez, he ate 3 plates of Muesli for breakfast instead of spaghetti. That goes through the system pretty fast.

40 km before L'Alpe he had to ... #2. 40 k before the end you can't get off anymore because you will lose touch with the peloton.

His 6 teammates pushed him, after one of them had gotten one of those caps they wear, from the team car....

You get the picture.