In other cases, like repeating elements, handling that server-side makes my head hurt. It can be done, yes, but it's going to hurt. You'll have to take control from the normal controller and do lots of fancy things behind the scenes. The alternative is not writing the form anything like that, and forcing another half-dozen clicks by the user to do the same thing. That's not a compromise I get excited about either.
I don't think that makes any sense in the modern web. I don't see any reason to aggressively make things harder for these people, and lots of things should work without problem, but I don't think that's a user choice that I'm going to work to support. There's lots of choices users can make, I can't account for all of them.# Ian Bicking