It seems to me that the business is in issuing certs. SET goes out of its way to use as many as possible. It's the one thing that the providers assert an exclusive right to.
Certs are the net version of the plastic card.
They're going to be branded and charged for. SET is the scaffolding of a Chinese Wall of branded certs around the network payment system. This message was sent by a majordomo-based automatic list manager. Subscriptions to and archives of this list are available to any person or organization.