If they're not careful they're going to endanger what access they have now. If secure communication as we know it ceases to be actually secure people will start (are now) figuring out how to go around points of failure. Meaning, if they push on this too hard they'll lose their ability to listen in on targeted communication because people will have more faith in unsigned than signed keys.
All it takes is one leak of this data to throw the entire idea "gimme your private key" requests into the domain of F###ing horrible ideas.
Actually, how crazy would it be if the documents that Greenwald is sitting on now bring to light that this is already happening... it would overnight throw software best practices into chaos. I hope he's careful.
All it takes is one leak of this data to throw the entire idea "gimme your private key" requests into the domain of F###ing horrible ideas.