I don’t think it makes much sense for the UK tbh. You get to maintain some very slight additional control over a handful of policy areas but, in exchange, you lose any influence over all the other areas of policy that come under Brussels’ remit. That’s fine-ish for Switzerland, which is small enough that it wouldn’t have much influence anyway. Or for somewhere like Iceland, where fishing’s a big part of its economy so it actually does make complete sense to trade influence in Brussels for staying out of the CFP.

The UK, being a particularly powerful and ‘looked-to’ European country, would be trading a lot of influence for very little retained autonomy. It doesn’t really figure. Maybe it could join EFTA as a prelude to rejoining outright but I don’t think the UK would find EFTA tolerable for long.