Continuing the discussion from YouTube footage of LGBT hate crime goes viral:
The general theory is that you keep reading as you reply, and your reply addresses several posts, with quotes of the relevant sections – so you’re not spamming the topic with 5 distinct, individual replies to 5 different posts.
But if you’d like a user preference that does not take you to the bottom (so you can see your reply) after replying, that’s probably fine. That behavior would probably confuse the hell out of the average person, though (as in: hey, I replied but where is it?), but since it isn’t a default that’s OK.