I think the only way PG would try this is if it's clear that javascript, client side hacks, etc are not required -- and I think that's the case. Aside from the

I think the only way PG would try this is if it's clear that javascript, client side hacks, etc are not required -- and I think that's the case. Aside from the header, there's only a relatively small number of variations for any given content, right? Showdead, ability to downvote, etc? So, each of these variations gets a distinct ESI URL. Like /item_$showdead_$downvote_$etc right in the internal URL, so any combination of these is a distinct URL. Only the first user to hit any particular combination would result in a request to the backend, and that could remain in cache until its content changed. No wizardry required.