User blog comment:Sannse/Don't Feed the Trolls/@comment-1709282-20120912162058/@comment-8-20120912180233

It depends a lot on how you do so - the tone and content of the message you send is important. If you leave a dramatic sounding "OMG we have vandals!!! The wiki will die if you don't ban them in the next two minutes!1!! They are evil and have made me so mad!!!!".... then that's definitely feeding. If you leave a message that's something like: "Hi, I just fixed some vandalism on a couple of articles, but the vandal is still around. Could you look please?", then that's much better.

As well as the tone, and the lack of drama (including resisting talking about the troll other than the bare facts), it's good that the message is directed at someone other than the troll. That also helps keep it calm.

And if you have the chance, a private message via email is better still.