Google also has all that and now and then their network explodes anyway when they do configuration changes. :) Certain configurations at a big enough scale are

Google also has all that and now and then their network explodes anyway when they do configuration changes. :) Certain configurations at a big enough scale are dangerous, just because you could hit a terrible corner case when you rolled out the change on 50% capacity, and lose all of it so fast that your magic automatic rollback is pointless because your infrastructure is burning.