Self deception is a wonderful thing and in pursuit of a concept he imagines was invented by the Sumerians (apparently they also invented glue, although that might have been more along the lines of cow gum than Araldite) the skipper has justified a lunch-time beer on the grounds of the exercise taken in the late morning.
Now, there will be those of a picky frame of mind who hold the view that a swim twice round the boat and out to look at the anchor accounts for about ten percent of the calories contained in the bottle imported from Belgium. ( for those amongst you still trying to work out the name of a famous but non-fictional Belgian it's Jacky Ickx) but for the self-deceiver that Is of no moment whatsoever. Well done the Sumerians !