RomeoTangoFoxtrotMike,
I think we are talking about the same thing. We need two things to happen. One the Spam needs to be blocked from ever getting though and two we need to locate the spammers and stop them.
The ISPs are the ones that can do this. They have the information needed on every account and they know which account is logged in on which IP Address. It is very simple for the ISPs to work to stop spammers.
Using Bayesian Algorithm Spam Filters will let them know who is spamming instantly and they can take efforts to stop them, but they do not do it.
After all, each account they stop is one less account paying the monthly internet access fees to the ISP.
Take Care,
Richard