I mean it will definitely do harm to businesses. The funny part to me is how ambiguous encryption can be though. Okay so Cameron wants to ban certain cipher suites fine. Then what? Modified Cipher Suites? How will the government know? What if I take DH or Blowfish and I happen to add an extra byte at the end? What if the byte is randomly generated by the estimated number of farts in Parliament at a ranfome time? I don't think there is a good way for this (at least in my complete ignorance of legal stuff) to be sustainable. Just as different as Rot 13 is from Solitaire we'll find other methods of encryption. Also what if someone emails or pushes a file to your device? What if the software is open source? The guy is really grabbing sand here. I could also use a mice park bench to lay on of this happens.