RomeoTangoFoxtrotMike,
Excellent post!
In short, spam filterning by ther recipient, no matter how clever it is, is ultimately no more than a sophisticated delete key. And hitting delete, although very effective in remoing the spam, has absolutely no effect on the spammer at all.
That is why I hate hearing people say they just delete instead of bouncing, etc. because they do not want to waste bandwidth, etc.
If we do not strike back, the Spammers win 100% of the time.
Take Care,
Richard