Man, if Quintana could TT he would be so much more of a stage race contender (dominator?)

Why is it that he is such an average TT rider and such a great climber? You'd think with his great power-to-weight combo he ought to be at least decent in TTs. I realize there are other factors but I can't think of any other pro cyclist who has such an extreme mix of great climber and mediocre TT'er.

Today he just gave away everything he won on the big climb and then some.

TT performance is dictated by w/CdA (drag coefficient), not w/kg. Being larger has less of an effect on CdA than it does on kg. This means that TT's are biased towards larger, more powerful riders. This isn't universally true of course as there are some small riders that have put out excellent TT's, but a short look at top TT placings in word champs each year gives you an idea of who is best.

Conversely, I'm impressed at how well Dumulin can climb.

If nothing else, cycling is an excellent example of how a group of similarly excellent overall athletes can have dramatically different specific aptitudes.

He finished 23rd out of 190 riders, so he is well above average, and he time trials well uphill. But I agree that he would dominate grand tours if he were a better time trialer on the flats.

Finishing placement doesn't really mean much. There's typically only ~20 riders really trying in the time trial. The guys trying for a stage win, and the GC contenders. The domestiques are all on a training ride, their job is to suffer on the other stages.

Quintana is just too small to be a good TT. Time trialing is largely about raw power. He has a really good W/kg, but that's because the kg number is small. The best time trialist are bigger riders (Cancellara, etc) who can put up huge wattage numbers.

i think the answer you are looking for is that there are fewer maglia rosa bearing riders pulled over to the side of the road
answering nature's call or respecting what is understood as a neutralized stage during time trials.

Colombians, as a general rule, have always been known as exceptional climbers but lacking the horsepower on the flats.

Fabio Parra would be the exception that I'm aware of.

Nairo Quintana weighs 100 pounds (45 kg). He has probably 3/4s the aerodynamic size of the big guys, but his power scales (almost) by weight. So if he is 3/4s the size but say 2/3s the weight, that puts him at a (2/3) / (3/4) = .89 = 89% of the power to aerodynamic drag ratio. Being off by 10% in bike racing is huge!

The beauty of bike racing is that such different body types can compete and excel in different events. Grand tours are the amazing melting pots where the different types can go face to face. Domoulin has shown himself to be a gifted rider with multiple talents, but he is going against a tiny guy who spent his life almost a mile higher than the high point of this race. The two of them shine in very different places.

Ben

Raw power vs power to weight. It's always the advantage of the bigger man, because their raw power will kill a TT, and it's easy enough to manipulate your W/kg (through whatever means necessary) by shedding weight, while maintaining power. Little guys can't really up their raw power, without other kinds of artificial/chemical help. This is the big deal with Sky. Froome and Wiggins were absolutely skeletal, but they held their overall power. Helped them magically turn into climbers while maintaining power for TT's. It's much more difficult to go the other way...from climber to TT powerhouse.

Does he ride a Quintana Roo TT bike?

Whatever the reasons, it just cost him the Giro. Perhaps the French route will favor him more than the Italian route did.

As I see, Quintana don't lose "Il Giro" at today's TT, but in the mountain stages, where he (can't??? don't want???) attack to Dumo until destroy him, as he did in the Blockhaus stage. Said that, I think the Quintana's TT of today was excellent due to his possibilities.
Regards