I'm curious

Do you think Nano bans known plagiarists? Like the ones who keep attacking the same fanfic story repeatedly?

It takes all kinds:

http://www.nanowrimo.org/en/forums/nano-rebels

unless you mean actual plagiarists, and then I don't know how they would police it.

Since you don't have to use personally identifying information, and since they only have a handful of staff, and since they never actually see anyone's writing... I'd have to say 'No'.

yeah probably not. I was just curious though.