I can't think of too many instances (in modern times) where a rider has been able to hold imperious form throughout a three week tour. Even Froome in his tour wins has been holding on at times in the last week.
They will all be knackered. Just depends who can grind it out when they hit those last few stages. Don't know if its watching all the one day races in the lead up, but the Giro always seems so much tougher than the tour. Those three stages to finish are brutal.
I can't think of too many instances (in modern times) where a rider has been able to hold imperious form throughout a three week tour. Even Froome in his tour wins has been holding on at times in the last week.