Perhaps a better indicator is to look at the Tour-Vuelta double; the Vuelta doesn't tend to have as strong a field, and a slower average speed, and so should be more reasonable to easy for a GT contender to be competitive for consecutive races.
But how many GC riders have had success at both in recent years?
2009:
Evans (Tour 30th, Vuelta 3rd) can't really be considered because of the disaster that was his Tour.
Gesink (Tour DNF, Vuelta 6th) can't really be considered because of injury.
2008:
Sastre (Tour 1st, Vuelta 3rd) would certainly count, but he was outclimbed by others at that race who lost time where they shouldn't (Valverde and Rodríguez). He'd blown most of his strength at the Tour.
Valverde (Tour 9th, Vuelta 5th) only targeted the Vuelta after making a mess of his Tour ambitions on Hautacam.
2007:
Evans (Tour 2nd, Vuelta 4th) competed in both but was less successful in Spain despite the weaker field and slower pace.
Sastre (Tour 4th, Vuelta 2nd) was perhaps the first you could really say performed better at the second GT AND performed at a decent level in both.
Remember, this is with a performance at the Tour and then at the VUELTA. Performing from the Giro to the Tour is asking them to be competitive at a race which is faster and has a stronger field than the Giro. That naturally makes it harder to combine the two.
We shouldn't forget that Evans also had a very strong April classics campaign. Asking him to hold top form for FOUR STRAIGHT MONTHS is asking a bit much, I think.
But how many GC riders have had success at both in recent years?
2009:
Evans (Tour 30th, Vuelta 3rd) can't really be considered because of the disaster that was his Tour.
Gesink (Tour DNF, Vuelta 6th) can't really be considered because of injury.
2008:
Sastre (Tour 1st, Vuelta 3rd) would certainly count, but he was outclimbed by others at that race who lost time where they shouldn't (Valverde and Rodríguez). He'd blown most of his strength at the Tour.
Valverde (Tour 9th, Vuelta 5th) only targeted the Vuelta after making a mess of his Tour ambitions on Hautacam.
2007:
Evans (Tour 2nd, Vuelta 4th) competed in both but was less successful in Spain despite the weaker field and slower pace.
Sastre (Tour 4th, Vuelta 2nd) was perhaps the first you could really say performed better at the second GT AND performed at a decent level in both.
Remember, this is with a performance at the Tour and then at the VUELTA. Performing from the Giro to the Tour is asking them to be competitive at a race which is faster and has a stronger field than the Giro. That naturally makes it harder to combine the two.
We shouldn't forget that Evans also had a very strong April classics campaign. Asking him to hold top form for FOUR STRAIGHT MONTHS is asking a bit much, I think.