Hey, I've been obsessing over Raving and Drooling over the past few weeks (naturally ;) ), one version that I've been taking a real liking to was from the Colmar boot. Instead of the synth backing Roger's vocals it's another person, but it doesn't sound a whole lot like David to me. I don't know what their band consisted of on-stage at that point, so it could have been someone else, but sounds a lot like Rick to me. I was curious what you all thought.

http://www.youtube.com/watch?v=UP86ulW7dNA

Deffinately David.
Listen to Cymbaline And A Saucerfull Of Secrets (Pompeii) and you will hear the same deliverance on the vocal.

Yeah, it's David. Though they did have backing vocalists with them on the French Summer Tour that year.