Ugh, I hope this does not happen, I hate the scroll-to-the-bottom-and-get-more thing. Particularly if the server is under heavy load already, you never know if there is more or if so how much, and it takes the scrollbar away from your mouse pointer once it's loaded another chunk due to the relative offset.

Maybe I'm missing something because I've never seen it before, but has anyone ever tried leaving blank space at the bottom of the first page relative to the total number of comments? It may work better on items of fixed length than comments, but even on comments it would at least make the scrolling a little less jumpy.

I'm confused by your reasons. With scroll for more, you would know if there is more- the end is the end, just like with pagination. And it's no worse than pagination in the "you don't know how much more" department, either. The pagination is a "More" link, it doesn't indicate how much is on the next page.

One would think it would be relatively trivial for "More" to become "256 More" or similar...

NOoooo!!! Anything but the Scrollbar of Sisyphus!

I'd not heard this term for it before, and it sums up the horror accurately. You have enriched my life.

The Scrollbar of Sisyphus breaks the back button (click "Back", browser remembers where you had scrolled to, can't go that far down, lands at the bottom, triggers second "page" of results) jumping to the bottom of the page, occasionally searching, and forces you to jump to the end of the page repeatedly to figure out where you were. It breaks nearly every UI expectation one has about scrolling (especially on a phone) and several that your browser has about caching.

Those problems you listed are implementation-specific, and not necessary conditions of the feature.

This still would prevent being able to CTRL/CMD-F for a particular term to see if anyone has mentioned it already, something I do a lot, and I imagine others do too.

This is true, but a little bit of js would take care of that.

Infinite scrolling screws with scrollbar behavior though :(

Not until you hit the bottom of the first "page", at which point you've resigned yourself to more content.

That would be the first instance of an ajaxy thing on HN I believe.

The upvote/downvote on comments and stories uses ajax i believe.

yes/no: it uses simple assignations to (new Image()).src.

Not sure why you got hit with the down votes, I always assumed it used "real" ajax.