Agreed. I bet for a mere $20 million (ok, maybe $100 million, who knows) they could setup an operation to create a man-made "controlled" leak on the ocean floor

Agreed. I bet for a mere $20 million (ok, maybe $100 million, who knows) they could setup an operation to create a man-made "controlled" leak on the ocean floor at 5000 feet depth. And then they try out various methods of stopping that leak. Take notes. Fine-tune. Then they stop the test. Document everything, train people, put resources in place to be able to implement the same solution when a real leak occurs.