1. How do you know what I know or have forgotten?
2. The root cause of a failure is the most important thing to understand in order to fix and prevent it from continuing to happen. You're bringing up lean, not understanding the root cause of a failure is in direct contradiction to lean.
3. Read the statement released from Toyota. "There is a possibility that certain machining debris may not have been cleared from the engine when it was produced. In the involved vehicles, this can lead to potential engine knocking, engine rough running, engine no start and/or a loss of motive power. "
4. If you're referring to some other problem, my point is there is a probability approaching zero that someone, even a mechanical engineer, looking at limited design specs and/or pictures on the internet could accurately predict failure occurring. They could guess, and be right, but anyone can do that.
5. A large portion of this board don't seem to understand that Toyota isn't changing their engine designs because they are bored, enjoy unnecessary complexity, or are too stupid to figure out how to design large displacement more powerful engines. They are forced into this by government policies that plenty of people here actually support, indirectly vote for, or are completely ignorant about.