I don't know which folks you're talking about, but not TiVo folks I've ever chatted with about this said anything like that. M-cards can simply handle multiple streams going in the same direction(s). The host device, not the CableCards determine whether it is a one-way street or a two-way street. That is not the case. The CableCards are for supporting decryption and channel identification information. They do not support ordering On Demand and PPV.