The Barnoldswick Declaration

The just-before-the-summit level of the Leeds & Liverpool after Bank Newton must be one of the most splendid sections of the network. Reminiscent of the southern Oxford but with tighter bends, an even greater feeling of remoteness and more rugged scenery.
I shared Greenberfield locks with Tom Bombadill,  the narrowboat not the character from Tolkien, and then called in at Lower Park Marina for diesel.  Unlike a certain Marina on the Macclesfield Canal they do take plastic and after filling up I was invited to make a declaration of how much duty I wanted to pay; it being made pretty clear that any split would be acceptable.
I never know what to do in these circumstances.  The recommended split is 60% propulsion on which full duty is paid and 40% "domestic" where a reduced level applies, but increasingly I wonder if anyone still declares this.
In three of the last four times I've filled up boatyards have put everything on the domestic rate without asking me and here again it was obvious that any duty I paid was voluntary. However, mindful of the fact that I enjoyed a career in public transport that involved spending large amounts of public money I feel obliged to pay some tax so I made an arbitrary declaration of not quite the recommended split, only to notice that the form I signed had the spaces for my name and that of the boat left blank!
I think boatyards have got completely fed up of the whole process but as any agitation for change would probably result in full duty being applied to all fuel it's probably better to just go on as we are.