The Hitch said:
Eddy Merckx riding as fast as Wiggins did in the tts and climbs of the Tour last year having won every race he took part in for 5 months, would not have been believable.
Comparing TT speeds 40 years apart is a nonsense given that in Merckx's day they rode on normal bikes in standard cycling kit whereas nowadays they do TTs on low profile bikes in aero skinsuits and aero helmets.
Comparing climbing speeds is more meaningful, though I don't think Wiggo was actually particularly fast uphill in 2013.
Talking of climbing speeds, I was watching a documentary about the Tour over Christmas and there was extensive footage of The Badger and his contemporaries climbing. What was really striking was that the cadences employed were visibly lower than are employed now, which I assume is because of the narrower range of gears that were available back then. (i.e. they climbed on big gears because given the requirement to have a 53*12 or similar as the top gear, technology simply didn't allow big enough changes between cog sizes for modern climbing gears to be accommodated.) Or maybe training wisdom was that it made sense to climb on a big gear, so that's what folk did.
I assume riders use lower gears and higher cadences now in some mountain stages because the number crunchers tell them it's more efficient, so is there a benefit for modern riders in terms of climbing speeds, all other things equal?
Obviously, such an advantage, if it existed, would be quite small, so it wouldn't explain EPO era speeds, but could it be big enough (along with better bearings and lighter frames/wheels) to mean that a 41 minute ascent of the Alpe now is the same power output wise as a 42 minute ascent back in the 80s?
Even if the gearing theory is invalid, I'd be surprised if modern bikes aren't sufficiently lighter and stiffer compared to 80s steeds to yield a percent or two reduction in speed for the same power to weight ratio from the rider.