Of course there are other ways to skin a cat - Caisse formed an echelon and put time into Contador in Paris-Nice, for example, and there was that bizarre Giro stage where the favourites bridged across to the escape on a flat stage and Pozzato won with Vino, Scarponi and others up there, while Evans was busy punching Daniele Righi.
Contador and/or Schleck can be worked over, but it takes at least two, preferably three or more top riders from a variety of teams to do it. We saw Contador worked over at Castilla y León, by three elite climbers (Igor Antón, Ezequiel Mosquera and Juan Mauricio Soler), which eventually allowed Antón to put time into him. At the Tour too much is riding on the race for riders to a) take the risk of attacking; b) work together to potentially gain time for a rival.
Again, it comes down to the old adage that the Giro and Vuelta have 10 guys who want to win, the Tour has 30 guys who don't want to lose. You find that people in 7th or 8th don't want to attack lest they lose that all-important top 10 position. Look at how it was Garmin who chased back the stage 16 attack with Horner and Plaza in it, so that they could make sure that the two didn't make it into the top 10 and threaten Hesjedal's position.
Contador and/or Schleck can be worked over, but it takes at least two, preferably three or more top riders from a variety of teams to do it. We saw Contador worked over at Castilla y León, by three elite climbers (Igor Antón, Ezequiel Mosquera and Juan Mauricio Soler), which eventually allowed Antón to put time into him. At the Tour too much is riding on the race for riders to a) take the risk of attacking; b) work together to potentially gain time for a rival.
Again, it comes down to the old adage that the Giro and Vuelta have 10 guys who want to win, the Tour has 30 guys who don't want to lose. You find that people in 7th or 8th don't want to attack lest they lose that all-important top 10 position. Look at how it was Garmin who chased back the stage 16 attack with Horner and Plaza in it, so that they could make sure that the two didn't make it into the top 10 and threaten Hesjedal's position.