I would not recommend this, no. I do not agree in a bigger government nor in such nannying legislature. Furthermore, I have no reason to believe that this would decrease the number of irresponsible dog owners of these breeds, as your proposal does not cover the case where one person gifts the dog to another (there is no enforcement guaranteeing that the new owner is certified). Finally, who exactly would be enforcing this, would a Dog Inspecter be allowed to detain you and take your pit bull if you don’t show your certification on the spot? What about if the dog resided only on your own property? The fact that there are so many questions about this makes me extremely suspicious that the policy would have the desired results. In lieu, I would recommend having a city where certain breeds are allowed, having a city where certain breeds are not allowed, and letting people move to the appropriate city, where those who live with the dangerous breeds accept the associated risks. But even this would not deter the number of irresponsible or unskilled pet owners of any breed, which really is the underlying problem of the “dangerous dog” argument.