Stiffness saving time/power is a very vague concept I don‘t think I have ever seen it proven properly.
I believe that both MVDP and WVA were on Shimano DA wheels. I have never ridden them, but the 60mm version isn’t too bad (as far as I have heard…)
Working in a shop 6 days a week, I have said the very same thing about disc that Chris did. It’s not there. The customers we have coming in with rub and other issues are non stop, and yes, our mechanics are extremely capable, with one working with engineers at Trek in the past. They are not where they need to be yet, despite the push of the industry. It’s one thing if one rides constantly in wet weather, but if it’s raining I’m not riding outside except for racing. I think in time the forks will flex less, the gap in the rotors will be wider to allow for more play, the pistons will be better and the discs will be better and more universal along with thru axle standardization. For now, I’m fine with my lighter, more aero rim brakes.
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Being able to go fast on a bike does not automatically equate to understanding how bikes work. Lots of pro riders have zero idea about how to do even basic maintenance, let alone understand more complex issues like power transfer and how bar stiffness influences that.
I have an Orbea Terra that I swap wheels between the OEM gravel wheels and a set of Prime carbon road wheels. usually when going from Prime to OEM I don’t have to do any adjustment, but going from OEM to Prime I just switch the wheel, loosen the 4mm caliper bolts, pull the relevant brake hard then tighten the caliper up with a torque wrench so I don’t risk stripping the thread. In an ideal world I wouldn’t have to do that but it’s literally like… two minutes a wheel? Worthwhile sacrifice as I’ve been trying to rationalise the bikes rather than get more. The Terra with the road wheels is plenty fast for me, I don’t race though and any weight penalty is definitely coming from my beer belly rather than the bike 
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But he will have ridden a lot of miles on high end bikes so is pretty well informed on what makes a good quality superbike. 
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I don’t know what I would want my bike to be like, if I had to blast up a mountain to win a grand tour and I never will. But I do know I want my bike to stop as fast as possible, if a car pulls out a driveway directly in front of me. Because I definitely know what that is like.
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Given the winning move almost always goes on one of the climbs and often the gaps over the top are small I would take 6s less climbing in a heartbeat.
The hardest part of racing is getting the gap. If you’re 1% stronger than me I can sit in your draft all day and might outsprint you. If a different wheel marginally improves your chances of dropping me on the steepest climb then I’ll never get you back.
Same reason I have no intention to buy disc brakes for as long as possible. I’m a big watts rider, sadly with big kgs too, so I have to not get dropped over the 10%+ stuff so I can make a move in a place that suits me better and gives me a chance to win the race. So I don’t want extra weight from brakes (or any risk of even losing a watt from rub when climbing short hills at 700W)
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No…that is exactly opposite of the point I am making. Riding a given bike a lot doesn’t mean you know what makes it a good quality bike.
Miles ridden and being fast does NOT automatically equate to product understanding.
Back when I was doing product development in the bike biz, I received resumes all the time from guys thinking because they were fast they were somehow qualifies to do product development work. But many of those guys had very little understanding of the mechanics of a bike, let alone how to develop a good bike.
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And if the race was only on that hill, you would have a point. But there is a whole stage that comes before that point where an aero bike is saving the rider watts / energy…so they may very well have that little extra in the tank to overcome a rider on a lighter bike.
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Side note, and one for the engineers: is it realistic to guess/hypothesise about what might happen if a major player decided they wanted to absolutely nail rim-braking tech? For example, revisiting and refining SRAM’s hydraulic rim brakes, revisiting and refining the old Shimano DA bonded alloy brake track, all that kind of stuff. Has it been tried and got nowhere? Uneconomic? Or has the industry simply chosen another route and packed all its eggs into that basket and couldn’t now turn the cruise ship around, even if it wanted to?
Edit: I apologise for the huge number of mixed metaphors in that final sentence 
So from someone who sees a ton of different bikes. Are these issues all present on MTB disc brakes also but it’s just that the pros outweigh the cons for that use case? or is there something different about the design of the brake systems from MTB to road that introduces some of these issues?
I ask cause I only have one disc MTB and one disc Road and I think I have similar amounts of intermittent rubbing on both (rarely) with little to no constant issues for either.
Pro racers often aren’t as kJ constrained as amateurs. So the portion before the winning move will be under their maximum ability (plus they won’t be on the front) which means that riding at 270w vs 268w before the winning move happens makes less difference.
What will make the difference is if they are capable of doing 800w for 90s and you ask them to do 801w.
Over on Slowtwitch, Tom A. was a long proponent of just what you are talking about…he optimized every aspect of rim braking he could. Used SRAM hydraulic calipers, Kool-Stop salmon pads and HED Jet 6 Black wheels (alloy brake track w/ special finish).
he swore by the combination…
I still believe that adopting hydraulic calipers would have gotten the industry 90+% of what people wanted from discs…primarily the feel of hydraulics. But it was very clear that consumers were driving the move to discs. Trying to swim upstream would have been nearly impossible…as SRAM found out.
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OK, but you are just making numbers up…whereas the actual data is pretty clear. Weight doesn’t make a significant difference.
Not to mention that there is a weight limit, so it is an even playing field re: weight.
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That’s interesting, because in an ideal world that’s pretty much exactly the setup I’d want.
Otherwise, totally agree. We need to recognise that if there’s a problem here, it’s one that we as consumers (as a group) have largely created for ourselves.
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Quite a lot of pseudo science here. You are saving 6 seconds of time over the whole 6 hour race with the lighter wheels. Not one climb, but on all of them combined. It is also only around 28 minutes of climbing in total and the wheels only save 2.3W at 600W.
The breakaway was 5 riders or less for the final 1 hour of racing, 2 riders for the final 45 minutes. You have hardly any aero shelter when riding with just two people, and deeper section wheels can easily save you 5 to 10 watts at the speed these guys are going. Ultimately, the race was decided in a 55kph sprint, where aero is infact everything, and the added inertia of wheels is negligible.
Also, aero wheels benefit you all the time, while the advantage of light wheels only comes into play when you go very slowly. The rolling resistance advantage is close sub 0.4 Watts.
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Except power and racecraft… 
I think the thing people often overlook in these situations is skillset: knowing when to make the jump, whose wheel to follow (and whose not to!), stuff like that. That has to be more important than almost anything else…
Don’t disagree with you about the maths on aero wheels, though; it makes logical sense to me.
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It is pretty clear that MvdP and WVA were doing around 400W for the final 45 minutes or so. If you only sit in the peleton and win the race on a mega steep climb/ mountain top finish, then shallow wheels are the way to go. But it was a 45 minutes breakaway with 2 people and a unsheltered sprint. Aero is pretty much all that matters here.
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Absolutely correct! Even if I had the engine that a Van der Poel has, he would probably outdo me just because he knows so much more about race tactics.
Nevertheless, we are talking of people like WVA, MvdP and Froomey here, and they probably don’t go up against too many people who don’t know what they’re doing.
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I think it can be overstated, which is why the discussion on rim v disc can get so heated!
There are many people who over react, particularly when it comes to what are regarded as safety factors in cycling. And when you look at the whole risk, the whole population of cycling the relative effectiveness of the controls we have start to fade in significance.
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