I think it's similar everywhere. IIRC from time to time here in Argentina when there are too many big changes, the legislature make copy of one old law with all the amends and add all the new ones and approve the new version. Let's say every 50 years or so, and not all the laws at the same time. So the "current" law is a mostly a mess of patches.

The main difference is that in Britain the judge decisions become almost-laws, so it's like a repo with too many people with commit right. I think in Spain the judge decisions have less weight and only the legislature has commit permissions .

I think such "ludicrous sets of patches" are very common in many jurisdictions. (At least in Germany they are.) I agree, though, git patches would be a lot nicer.

It's not messy. You have to take into account that every patch is voted separately - read Robert's Rules of Order for an enlightenment ;)

Also the principle of common law.

Let's hear your solution to the mess.