The Comcast access points do, at least, have the saving grace that they're on a separate network segment from the customer's hardware, and don't share an IP add

The Comcast access points do, at least, have the saving grace that they're on a separate network segment from the customer's hardware, and don't share an IP address or bandwidth/traffic limit with the customer. Tesonet and other similar services (e.g. Luminati) don't have that. As far as anyone -- including web services, the ISP, or law enforcement -- are concerned, their traffic is the subscriber's traffic.