Wow, how very interesting. I don't know who's right, but having just listened to the linked page with the 'slowed down' / 'corrected' speeds, I much prefer it to the RJ we usually hear (who was already great). At the slower speed there seems more of a groove, and more soul in the playing, to me at least on first hearing.

Don't think speeding up is a thing of the past either. 'The Complete Brass Monkey' (which was complete at the time but isn't now, of course), their first two albums, was speeded up to get two albums on one CD. How do I know this? A certain member of the band said so on stage. He said he hadn't told us this, so I haven't told you this, either.