Everything exist on demos, before they get to the studio to record the album, they have demos made before.
Mk and Guy are recording demos right now, when the band, or other musicians come to complete the songs, they are the record.
I think that in the case of Lions and Communique (the song), it's not sure that a demo
recording exists
in both cases, the song was composed and written in the studio, during the album recording. So they rehearsed it, tried few things and then recorded it directly I believe.
It's a litlle bit different than demos completely recorded and "produced" almost like a released recording, like the case of 77 demos, or autumn 78 demos
of course now things are different, Guy and Mak can spent all the time they want in studio, so they can record and mix at many different stages during the album recording
Jimi Hendrix recorded tons of demos because he couldn't write his music, but I'm not sure it's the case for all artists all the time.
And it depends on what you call a "demo"
it can be rehearsal recorded, a jam recorded, a self-made recording in a hotel room, an alternate mix, only a different overdub, etc...
for example on "gloden demos", I make a difference between DWB or LOTW which are the final recording without lead guitar overdub, and no wonder he's confused or secondray waltz, which are works in progress, attemps, or whaterver you could call it, but all songs are under the name "demo"
here are "studio outtakes" from floyd' animals :
http://www.gilmourish.com/?p=4953Someone could call them "demos", but it contains many final tracks from the final release, so it's not completely "demos" in the way I quoted the WDYTYG form the MFN comp which is a completely different recording from the Nassau sessions
