It would be nice if it was easy to "place the HTML where it belongs", but in a complex app it's never just-replace: you have to preserve a lot of state, wether

It would be nice if it was easy to "place the HTML where it belongs", but in a complex app it's never just-replace: you have to preserve a lot of state, wether it is filters, forms, user selection, scroll position, ... so updating live becomes quite a huge work. I've seen good attempts with libraries like idiomorph, but still quite some plumbing to do depending on the app.