Yes, but MNHQ have more information about the poster than we do. We may think it is a newbie, but it could in fact be an old timer.
Or, they can see immediately that this is a newbie. In any event, I dont think it would be a question of straight out banning.
How they respond to the reports would be to their discretion. If Lapin were to troll, I am sure she wouldnt be banned, but get a slap on the wrists a la "Oi there Lapin, you know better than this, now stop it, or else.... " email from HQ.
If a newbie were to troll, there is no saying she/he would be banned right off, but could receive a mail saying something like " Hi, Welcome to Mumsnet, I see you are getting a lot of attention from your thread today, may I refer you to our troll policy, and ask that you please refrain from this kind of posting behaviour if you want to continue using the site", etc. So, a warning, and if the warning is not headed, then a ban, maybe?
I think MNHQ needs to formulate an internal troll policy, and classify trolling.
- Humourous Trolling
- Malicious Trolling
and
A. Newbie trolling
B. Old Timer One off Trolling
C. Serial Name change Troller
And work out a Response and Escalate procedure internally, based on the early warning system (us) and existing knowledge.