I'll take a stab at answering this by paraphrasing Musk. He said this 5 step process was inspired by the time they were trying to optimize part of the Model 3

I'll take a stab at answering this by paraphrasing Musk. He said this 5 step process was inspired by the time they were trying to optimize part of the Model 3 production. There was a segment that was causing a lot of problems - the installation of some sort of foam or padding on the battery. I guess the glue wasn't adhering well between the metal of the car and the foam, or whatever I dunno, problems. They tried all sorts of things to optimize the process, until eventually Musk asked, "what's this for?" and the Noise and Vibration team told him they weren't sure, probably for fire safety. The Battery team (the one that would institute a fire-related requirement) told him they weren't sure, it was probably for noise and vibration. They built a car without the foam, tested it for noise and vibration against a car with the foam, couldn't tell the difference, and ultimately removed the part entirely. So this story touches all 5 of the points, but on the point of "make the requirement less dumb" it means that whoever got the requirement in the first place should have asked "what is this for?" and should have tried to find another way to meet the requirement without needing foam (and in doing so would have found out that the requirement was BS in the first place).