It's not pointless, there are many in this thread that disagree with you. A system of compulsoruy registration is more to be enforced by a fine if it isn't complied to. I really don't see that as a problem. Plus it will provide a pot for those who are attacked by an uninsured dog to gain compensation in the exact same way that we can get compensation if we are injured by an uninsured car.
Whilst it's obvious that keeping a shamu in 'cage' is going to require extreme caution, I do find it mildly amusing that at the same time people are relatively reluctant to accept any potential dangers of certain dog breeds.
I'm starting to get concerned about you, you seem to have suddenly leapt towards a belief that the government needs to control every aspect of people's lives, and that all government interference is beneficial no matter how over-zealous and draconian it is. You seem to be taking the irrational 'preventing one incident is worth punishing millions' insanity that pervades authoritarian governments worldwide, while ignoring the fact that it won't actually address the problem issues.
What changed Nitefly?