GURPS Dungeon Fantasy Setting: Caverntown

[Evil Roy Slade]

Originally Posted by Kromm

Note that GURPS doesn't assess special FP costs for stair-climbing at any pace. The "extra cost" comes in through the extra distance (doubled!) and thus extra time (also doubled!). Hiking costs a few FP per hour, so fatigue just won't be an issue here.

This is, I suppose, the heart of it: though GURPS is plenty robust, I am not sure anyone at any stage from 1986 onward has given much thought to how well the mechanics capture the situation when a character is running up essentially a mile of vertical staircase. With all due respect to your calculations, I think I will go for something more plausible, heroic fantasy or no.