If it *actually* worked right, why do I *ever* encounter people that don't even know what block lists they're using?
As MAPS found out during some early legal imbroglios, it is very easy to convince a judge that at least one ISP has subscribed to a blackhole list without understanding the full effects that this choice would produce. The whole "click to agree" (or "press F8 after scrolling to the last page") thing from software vendors is no better. There's no way a judge (nor, one assumes, a jury) will ever believe that everyone who signalled agreement, understood. The last couple of times I've signed closing papers for a house I've had to write several times "I agree, and I understand english" longhand and then sign my name -- but I don't think that'd hold up to a challenge of nonunderstanding, either. Every non-P2P non-anonymous reputation system will be vulnerable to this, and every P2P or anonymous reputation system will be full of sludge. We don't have a mature enough system of accountability, anywhere in meatspace, to account for the kinds of relationship and transactions the Internet makes possible. -- Paul Vixie