Ok. I recently installed an add-on for Firefox that lets me browse through image galleries automatically without returning to the index page. (A feature of Opera)
But one of the options on this add-on was "Decrement URL --" and "Increment URL ++"
Just for fun, I tested it out when I was looking at a thread. All it did was increment the number for the Forum, but kept all the other URL info the same.
So I was viewing this thread:
http://ffxi.allakhazam.com/forum.html?forum=22;mid=1237081435298356560;num=3;page=1
And I hit "Increment URL ++" until it sent me here:
http://ffxi.allakhazam.com/forum.html?forum=28;mid=1237081435298356560;num=2;page=1
Same thread, but in the OOT forum. Just for kicks I posted a reply, and it worked. It registered as a reply to the =22 thread, but only shows up on =28.
I noticed the exact same thing happen if I post when an Admin moves a thread.