'cleverness for its own sake' often makes it into standard practice later.

And I seriously fail to see the 'for its own sake' here. This cleverness reduces the number of moving parts, does the 'dont repeat yourself' and thus reduces ways modifications of the code could break it due to overseeing a case.

I just shuddered to think how this would be done in java - with a LinkUpdater interface, and a RootLinkUpdater and ElementLinkUpdater, and one instantiation per iteration, and suddenly we have a lot of code around to keep the active code's function simple - to a point where it is completely pointless because of adding a lot of machinery. (And java does collections differently anyway.)