> Is it strictly-true that anti-spam algorithms must be hidden to be effective? Can't answer that but there were, for a long time, services that would run your

> Is it strictly-true that anti-spam algorithms must be hidden to be effective? Can't answer that but there were, for a long time, services that would run your "targeted emails" through spamassassin et al for you and give you advice on how to tweak them to lower the resultant score.