I would agree.
I was on a web forum a couple years back that had a smut posting troll on it.
Took us two or so months of documenting the troll's IP addy, behavior, and posts, but we got them permanently barred from having internet access legally.
But we had to document everything.
Using free e-mail addies doesn't stop the troll from broadcasting his ISP addy, IP addy, and various sundry other bits of information.
Besides, the troll on teh board previously mentioned tried that.
The e-mail provider was kind enough to hand over the information on the troll that they had, their regular e-mail addy, the ISP and IP addy from which they'd registered...
I'm sure the mods and Jim have thought of that.
You see, we tracked that troll down to a webTV account.
They'd used a library to post smut from, but they'd registered the e-mail addy from home, and another one from work.
Oops.