I wonder if they're keeping fixing this as a backup plan for a rainy day? Say one day UK's GDP goes down harder than they'd like, so in order to burn some money and boost it back without making it look obvious, they'll announce the country has made up its mind, and is switching to full and proper metric starting next year. Cue the economy going to overdrive, as everything and the kitchen sink has to be relabeled or replaced...
(And if that doesn't help for long, they can stimulate the economy further by changing the driving side to the right one.)
It’ll go the other way: the next time they need to leave something, they can have a referendum to leave the metric system, then go through a few governments to get it done.
Actually, I'm Indian, and we have our steering wheel on the right side, just like the Brits. It's one of the less fortunate things we picked up from them.
(And if that doesn't help for long, they can stimulate the economy further by changing the driving side to the right one.)