I go to a monthly workshop in Rainford Lancs. which focuses on playing for dancing.
I would suspect that it doesn't matter what Les starts out doing with his tune book, people will end up contributing a variety of tunes, from a variety of sources and there will not be a standardised way of notating.

The other oddity when writing music is that the lead note is sometimes played in the repeat and this may make the last bar 'wrong'. E.g. you may have to hold the last note for a different length of time when going from B1 to B2 / B2 back to A / B2 and out. A trained musician would notate it with complicated 1s and 2s (over the last bars), someone who plays by ear would get it right. Those of us in between follow the dots then trip over when 'eyes' and 'ear' tell us something different. Until we know the tune.