Thanks for accepting the server side Spam filtering has some merit. I agree, it's not for everyone. BT's implementation allows automatic kill, or file for checking. I set my BT account to file for check. I believe it builds a model of what is really spam based on user decisions over time, and stuff marked as Spam has a much lower server side retention time.
My intention in making the original post was to offer a constructive comment to NTL. That's still my honest desire, a gift to NTL, an observation designed to foster improvement of service. I've tried by eMailing NTL directly but I don't think the message got through.
Why I have a BT account is not really germane to this conversation, but in the interests of transparency I'll answer. My BT account is historic - dates right back to 28.8 over dial up as the state of the art. I have no great love for BT. They have their faults as well. They mistreat their customers, and often act with high-handed arrogance, and very seldom act on customer comment. Behaviors which seems to me (in varying degree) are par for the course with ISPs. Why am I with NTL - simple - it's convenient. My area was originally cabled for TV by my local council. They sold the franchise to Cambridge cable. When broad-band over cable became available connecting was convenient, and the spin off's also worth having.