I think just about every fixed formula ignores so much context it's in. In my opinion the disadvantage a lone rider has over a strong team until the final 5km is pretty disqualifying. Col de Portet had none of that and Quintana launched the winning attack on the bottom slopes. Now that doesn't mean AdH type clibms are all harder but I definitely think the Col de Portet is harder.
I think the most important trait of a climb is probably the altitude gain on a climb that happens on gradients over 9% or something. Preferably not before too many stretches of 6% and lower where team strength is quite dominant.
Now 2 big questions I'd have are the actual importance of altitude and how it matters. The stage in question only goes above 2000m for 3km or probably 11-12 minutes, so I don't think it's that important. The 2nd part for me is the effect of climbing longer distances under threshold values, and I think if they go under riders won't be that affected by earlier efforts on the final parts of the climb. It's what the entire tactic of bludgeoning a climb with a strong team and strong leader is about that everyone else blows up but your team leader.
Jumbo won't blow up Roglic, UAE can't blow up Roglic.
So Letras scores 0?
