I think the biggest requirement in CX is to have a big engine, as most courses favour those riders and she has that. Anything after that is a bonus.....and she's far better technically than she was 4-5 years ago; being on Sven's team has worked for her. I suspect the same applies to Shirin.
I've often said, that if you're a lightweight climber, then CX isn't a sport for you.....a handful of climbing courses over 5 months isn't enough.
Agree completely. Brand vs Alvarado is a great example of the big engine vs great skills. Of course Alvarado also has a big engine but still smaller than Brands and of course Brand isn't a complete beginner but have some CX skills on her own. It's the relative ratios, and then I would also go with the big engine.
Another example that comes to mind is Tom Meusen that seemed to have super skills but not an engine that could match the other top riders. Once in a while he did good results but often not.
And yes lighter riders might have a disadvantage but Iserbyt (1.65m/56kg), Pidcock (1.70m/58kg) and Van der Haar (1.69m/58kg) are quite small and light so some things are in their advantage apparently (acceleration, corner speed?)