Hello Jammer,

One thing comes to mind here, the granite blocks in question are not (as far as can be determined) at all finished or polished (this has been mentioned elsewhere).

Then my school-boy physics (which never got much beyond that Greek chap splashing water all over his bathroom floor) has me wondering about the sheer weight of the blocks having a braking effect - or what the technical term is.

The limestone of the Ascending Passage roof and floor is comparatively soft (one early adventurer is said to have removed surface flakes with a knife) but the floor is very hard.
But I'm told that this hardness is a result of thousands of pairs of feet trundling up and down the Passage for hundreds of years - the implication being that originally the floor was, like the walls and roof, comparatively soft.
I imagine this, too, needs to be, how shall I say, part of the equation.

MJ