I didn't mean to be "that guy", but managed to post the same thread multiple times. The way it happens (it's happened before) is that I type up something, hit POST, and nothing happens. The page remains static even after a few seconds. Thinking that perhaps I didn't actually hit Enter, I do so again. Most of the time that will work, but sometimes even then it won't. The next morning I see that some idiot has three threads all with the same title, something about selling his book. Well that's an obvious spammer... only it was me this time. Apparently there's a time limit on deleting threads because that didn't work.
Strangest of all: After posting, I wondered if I'd left multiple threads and checked the main page. Nope, it showed my thread once. Next morning, there it was, three times.