In reply to LeeWood:
> What particularly interests me here is how our choices, attitudes and preferences are traceable to discernible elements of mental capacity: patience, attention span (boredom), capture and memory, comfort with risk elements etc
I'm sure there's a strong connection there. But I don't think you can discount the fact that people run out of easier routes to do in a fairly short space of time. I'm specifically talking about sport climbing here - which what redpointing is about anyway. Sport climbing happens at a much faster pace than trad. There's no belays to set up, no second to bring up, and the pumpy nature of most routes means you can't dilly dally around the way you can on trad.
Unfortunately this means, in a country with comparatively little sport climbing, it doesn't take long to get through all the routes you can onsight. After that the only choice is projecting. The easier projects don't take long. You can get through several 'second try' routes in a day. After that you soon have to move on to the multi day projects.
Some climbers spend years going up to somewhere like Malham trying the same things. It's not necessarily that they're desperately wanting to climb the next level or don't like onsighting. It's mostly a case that they simply don't have anything easier left to do.
Take those same climbers to some big European crag they've never been to before and it's a fair bet most will spend a good percentage of their time onsighting.