Well so far no problems. I may have actually been clicking on my own reply instead of the other person's... I don't know for sure.
But seriously, I really want to know why that is even a feature? Why can't the owner just hide, remove, or disable it? The only purpose it seems to serve is screwing up the PM convo. Seems like enough people in this thread alone have mentioned it as a problem enough times to consider doing something about it.
If that's happened it wouldn't be the first time. It's happened to me before. Seems like a lot of forums either have the reply link/button at the top or at the bottom of each message. You get into the habit of doing it one way, then that habit screws you over in another forum. lol