That way output where the colour isn't appropriate, such as Nook or the newly introduced
A4Lulu output (which is the A4 book but with white cover page and no end coloured page, and so
suitable for using as the content on Lulu, where the cover is separate) can omit the colour.
A lot of stuff was being duplicated between different page size. Consolidate where
possible, and in particular put as much into a single source file (dottes.tex) as
possible. Making a single Booke is now potentially quicker, as the tune pages
don't necessarily have to be regenerate every time.
Jim Hague