Quote Originally Posted by Kranel_San View Post
In which it would also be used to blacklist all the players who're starting doing PvP because they're not skilled enough. ...

If Blacklisting players would stop them from being matched with you in DF then this may results in a longer queue time from either your end or theirs, ...

... So in the end there is no reason to stop someone from being matched with you in DF. It can only cause harassment ( Mass/Encouraged Blacklisting on a player )
Mass blacklisting seems to be mostly a JP problem. Anybody who tries it in NA tends to find out they're the ones that can't get a queue pop.

There are far more serious concerns (stalking) than avoiding bruising somebody's fragile ego. Gods forbid anything tragic happens but the way Square has implemented their system is not going to impress many judges.