Don't you think there is always going to be an escape hatch for peoples private data? Like if you ask it how to make an explosive the message won't stay private on Google's servers? Seems like there could be all kinds of things like that.
replyThe design on the system is specifically done to make that impossible because you control the encryption keys and they can't see your data.
replyIt nearly works except for the annoying hardware signing keys.
With OHTTP it might still be ok because it is impossible to identify which server has your content. OHTTP probably still applies to the Apple->[Google+Nvidia] version but they haven't specifically said that.