Like I said, I don't think it's unreasonable to trust Apple or the Tahoe LAFS download server. I think they're improving the state of security and I would use those products. I just want people to be clear about the actual security properties of the whole system.

For example, people should know that blanket statements like "Apple cannot read your messages" are false. And your client/server protocol can be state of the art, but you still rely on the much-maligned HTTPS certificate infrastructure (among other things) to get the client bits.