I think at Langdale at least, it would make sense that the roughouts were done near the top of the scree, as you'd get pretty hacked off if you'd lugged a basket of scree down to the valley, found that most didn't shape well, then had to go back up for some more.

From an economy of effort pov, roughing in situ (or in the closest shelter) would mean that you could easily discard the crap bits, and would only have to go to the bother of taking the good rough-outs down the way for polishing at your leisure.

It's also possible that the roughouts were traded, and that the polishing was done elsewhere.

No sign of that bullaun thingy FW, not that I had much time to look.