Not saying it is a bad idea, but the way it works is it ensures certain things happen that you would normally want to happen, namely: * test of a rollback proc

Not saying it is a bad idea, but the way it works is it ensures certain things happen that you would normally want to happen, namely: * test of a rollback procedure, * developers thinking about backwards compatibility and rollback procedure. The main issue I see with this approach is that the test of the rollback is only partial. Just because the schema is usable by the previous version of the application does not mean the new data that is going to be put by the application will perform the same way. Another issue I am seeing is that it is not a separate testing event but essentially happening live when the application is turned on on production. Not nice. On the pros, this is very useful when you want to have more than one version of the application code to coexist at the same time. But I would not rely on learning about incompatibility when I start deploying the application, I would want to know that well before then.