yeah, for a moment I was reading it as being a holomorphic encryption type setup, which I think is the only case where you can say 'provably private'.

It's better than nothing, I guess...

But if you placed the server at the NSA, and said "there is something on here that you really want, it's currently powered on and connected to the network, and the user is accessing it via ssh", it seems relatively straightforward for them to intercept and access.