When I buy a calendar entry, I'm buying that - an entry - a place on the ride, with access to its resources, and its validation.
When I buy a DIY perm entry, what am I buying, the entry or the validation? If it's the validation, why should I not be able to reuse the brevet if I don't use the validation?
I don't think calendars and perms are the same thing at all. It might be consistent and tidy to treat them the same, but I'm not sure it's entirely fair as they are not the same thing.
But after all that - FFS, it's just £4 (or thereabouts). How many DNFs does a career Lonely Heart DIYer have in a year? Not many.
Edit: It would be interesting to know how many DIYers are under the impression that a DNF'd brevet is not reusable, as I assumed it was
.
Also - I really hope Ashaman42 doesn't mind his/her thread being reduced to the customary mush that is the wonderful world of AUK rule ambiguity.