I finally figured out that there's a setting to change default sorting behavior, so my annoyance at it never being remembered (neither in-thread nor globally) when setting it in a thread is aleviated. However, there still seems to be at least two things not working as you'd expect them to/as they should: 1) If you set reply sorting to "new" (i.e. new at the top) and you reply to a thread, your reply ends up at the very bottom of that thread, despite being the newest thing in there. You'd expect that to be shown at the top where it belongs. 2) If you use classic view, rather than nested, the entire sorting seems to go out the window in that replies to posts, rather than the original thread don't get moved at all. Would be nice to get those moved to the top (again, using sort by "new" as an example) with only the already read lead-in collapsed, grayed out or whatever by default. Otherwise it seems you basically have to scroll through the entire thread to find whatever sub-reply might have been the new one.