"unpredictable in behavior" No more so than any other breed of dog. Dogs very clearly can communicate with body language, but if you don't understand it than yes, dogs in general are unpredictable. Just the same as a human speaking a different language will be unpredictable to you. If you take the time to learn dog body language you will see that dogs "Say" quite clearly when they are happy, sad, nervous, uncomfortable, want you to back off, ect. The only time I've seen a dog be truly unpredictable was do to a medical or mental issue.

"unnecessary" I know quite a few Pit Bulls that have very important jobs such as being a Service Dog, Therapy Dog, and even a Police Dog. They also do well in many sports such as weight pulling (You can find Pit Bulls in really any sport) Along with just being great pets for some people.

"They don't hold up if you examine them" which ones? I posted some very reliable information.

I wouldn't count an insurance company as any sort of "Evidence" Nor are news paper articles which report anything that gets them readers. News articles often get things wrong.

If you talk to anyone involved in the Pit Bull breed (Breed rescues, breeders, trainers, ect) most will agree that they are prone to dog aggression. They were bred to fight dogs, just like Retrievers were bred to retrieve.

Honestly, though it many sound harsh, we can't bubble wrap children. There are many dangers in this world and we can't possibly ban everything that might be a danger. I've been attack by dogs a few times actually (None of them Pit Bulls) yet I have no desire to ban any specific breed or dogs as a whole. The only issue I have is with owners who can't control their dogs.