Additional comment to my question why this may be important is following situation
in reply to Does perlmonk.org users are analyzed?
Say, I saw a node which contains bad information, so I decided
to downvote it.
Okay. But author of it (say) has enough power to see it was me
who dislikes his node.
Then it became angry to me and downvote everything that
belongs to that user (me).
It's not a secret that when massive downvoting happens,
people tend do downvote several nodes, even brilliant ones without reading.