Encryption on Mailing lists sensless?

[Robert J. Hansen]

> I agree with several other important points you raise, but this one is not a big
> deal. I have a highly customized mail setup. My SpamAssassin downloads rules
> from the internet, but trains its Bayesian filter on only the e-mail I
> personally receive.

I don't mean to sound like I'm dismissing your experience, because -- 
well -- your experience shouldn't be dismissed.  (Nobody's should.)  But 
I do think you might be overlooking something: you already experience a 
significant benefit from the aggressive, God's-eye-view anti-spam 
efforts of Google, Yahoo!, Microsoft, and more.  The things they do for 
their users have a ripple effect in making your own anti-spam fight a 
little easier.

A couple of months ago Mike Hearn wrote a brilliant treatise on 
end-to-end cryptography and anti-spam technologies, with a long 
digression on how anti-spam technologies work at Google.  It's worth 
every second it takes to read.

https://moderncrypto.org/mail-archive/messaging/2014/000780.html