Its also possible to take mental note of how many replies there are in a thread. If I am following a thread and I notice "ok its at 18 responses, 2 pages" than then see the "new" button I look, oh, its still at 2 pages, and the latest post wasn't the OP. But here's a new topic that looks interesting. I'll read the new thread first. Later I might see "wow, that other thread is up to 33 responses, 3 pages" and check out where the conversation has gone.
I've been doing that with the stolen turkey dinner thread - lately I only check it every 10 or so posts... unless I see grammarnerd posts, then I'd check it right away. If requests for updates bug you, once you see that's where a thread is going, just don't check it as often. If new posts are slow, its probably a request, if they suddenly spike, its probably due to an update.