In reply to yoshi.h:
Having climbed on SS for many years, and had some input into Climbers' Club the guide (and moderated the main SS crags for UK Climbing until it was taken out of my hands...) I'd suggest that the SS grades (UK Technical) are generally in line with other UK venues (I can't really comment above E3/E4...).
The grades on SS have evolved and have been adjusted up and down a bit as newer guides appear but not much changes really. The grades are probably the result of a few attempts and certainly, for more established routes, the result of a consensus but I can think of quite a few routes that would be tricky to justify for an on-sight ascent.
The UK tech grading has been in use on SS since the first guides appeared back in the 1920s but I suspect it was tempered by the Morins' experiences in Fontainebleau.
Isolated areas such as SS seem to develop a local calibration to the grading system and the fact that there are now so many makes reading across from one system to another almost impossible to be accurate or truly meaningful... And now the Rockfax guide to SS has introduced Sport grades - Why???
Cheers,
Graham.