You are indeed correct tonyw, A kestrel for a knave was the original book it was set on (which for some unknown reason, I haven't actually read) I wonder what our friends from over the pond think of it (aristo & Syzzie)?
When I used to work as a postie on night shifts, me and a mate used to quote the lines to other workers, they had no idea what we were going on about. If people were skiving in the brew room (including us) we would bellow "Slack work lad... slack work" and if people had different coloured coats on, we would always come out with the favourite "We'll be Spurs sir, so there's no clash of colours". It is strange what you resort to on long night shifts. Glad it took you back there tony.