Not only is this stupid... (Score 1)

It's impossible to enforce an encryption ban in all it's forms. While the UK's government could in theory try to ban obvious encryption, they can't necessarily detect and stop every kind of encryption. Good people have obvious uses for encryption, and obviously would try to use some for security. One way I see is to use mimicry, where communications are encrypted to look like a plain kind of communication like poetry or spam. This kind of communication is pretty hard to "prove" that it is encrypted. All you can tell is that it looks suspiciously similar to previous messages. But that isn't grounds for anything. I would love to see some government monkeys try to prove that that is actually encrypted. For additional fun, the messages should go though normal scrambling encryption before mimicry, then, not only does it not look like it's encrypted, but it actually is using the kind of encryption they banned. And the prime minister can still read their terrible poetry.