Have you read the book The Design Way?

I know someone who thinks it is really insightful. In skimming though it, I see little that is not fairly obvious. I am skeptical of high level books that tell how to do everything. Having said that, there is one important design principle I learned as a programmer, which was not obvious at the time – design for testability at all stages. In areas other than software or electronics, this could relate to building prototypes and doing test marketing. I did a search in the book for testability and did not find anything. It could possibly be listed as another name.