Hi Desdemona,
It's not that difficult to tell Roger and Dave apart really. Dave's the one who CAN sing and Roger's the one trying desperately to sing. (Rog couldn't sing his way out of a soaked paper bag.)
Also, I believe if you look at the Lyrics & Discography section of this website and scroll down, you'll see who does what. I think.
Oh, btw, welcome.
Floyd on!
Byron
p.s. that fixxlevy geezer gets all the plaudits. :sad: