Terpstra won the RVV because he decided to follow up on his doctor's advice and drop 2kg, because that way he would be able to deal better with the succession of short climbs. The freaking RVV, not 30 minute climbs. A quick succession of short climbs can be tougher than a 30 minute climb at the end of an easier stage. And yes, weight also plays its part on those.
I never said that mass doesn't matter on short climbs, only that it's not the issue here. Evenepoel did way better on Itzulla climbs while probably weighting more. In Norway he looked skinnier than before, had his best ever climbing performance and now suddenly mass is a problem again? It doesn't add up. Either there's a particular reason (illness, dehydration etc) or his form really dropped after spectacular form for a prolonged period (from LBL).