In reply to Mick Ryan - UKClimbing.com: What needs to be added here is the question of mats!!!!!!!!!!
For sure, the wee route I soloed in Spain would be fine to fall from the crux with a pile of big mats and a spotting team (as in highballing). Above that you would still be on your own though - when someone else solos it they can say whether this is easy or not, I found it the scary part of the exercise (the move to the shake out). But I did it solo - no mats or spotters. it was about E9 6c in british money if that helps people make sense of the difficulty (it seems to be the obsession, which is really sad).
The fly was highballed with a big mat pile and spotters and fallen off loads with no problems. This shouldn't be hard to understand for anyone who's climbed on grit - I had a fun afternoon with some mates many years ago, taking turns to lob gleefuly from the crux of Ullysees at Stanage onto four mats. But without any it's completely different and has caused at least one set of severe fractures. Would The Promise be E10 with mats? I smashed my ankle to bits from 6 metres at the roaches (the one foot that missed the mat) and was still in plaster three months later.
For grit sized routes, highballing is increasingly possible with mats instead of the rope as protection. But if there is no protection, you can't really fall off.