1. This is a gray area. If the link is a genuine link to a proper discussion on a site that you do NOT own or affiliated with, then that is fine. However, we have in the past have people from other forums post links to threads as a mere means to get more traffic. That would be against our rules.
Or maybe it has roots in the behavior of trolls of the dark ages....
No trolling could mean that "This forum will absolutely not tolerage twisted, short, or disfigured and otherwise smelly or poorly behaved individuals who hide under bridges tending to jump out and harrass innocent and well meaning visitors