I wouldn't readily lump Indurain in the same sentence with Armstrong in this particular context. Indurain won the Tour and the Giro twice in the same year and I believe podiumed in the Vuelta the same year he won one of his Tour's so unlike Armstrong he did compete extensively in more than just the Tour. Armstrong during his 7 year run may have won a couple of week long stage races but after the Tour was over his season was over too. Leading up to the Tour, as you mention, everything was prep for the Tour.benpounder said:Armstrong, and to a lesser extent Indurian, set the TdF as the preeminent bicycle race. If one fancies their chances at a podium finish, all other races are really training.
As far P-N losing its luster so to speak, as stated earlier, its a sign of the times. ToC has grown to the point where European riders look forward to going to Cali (The women? The sun? Ha Ha!!). Numerous teams also use Cali as their early season training site.