is a separate gdp branch useful?

[Graham Percival]

Initially we wanted lilypond/gdp on a separate branch so that we could 
tear apart the docs while keeping the 2.11 docs intact.  But since we've 
merged the docs now, is there actually any point in keeping them on a 
separate branch?  Would a separate branch just make more work for John, 
for now real benefit?

Cheers,
- Graham