Kelly Johnson, head of Lockheed's Skunk Works, worked on the P-38 (as well as U-2, Blackbird, and the F-117A).
He had a list of rules for managing the design of aircraft. see https://en.wikipedia.org/wiki/Kelly_Johnson_(engineer)#Kelly....
There's an unwritten 15th rule (from the above-mentioned webpage):
"Starve before doing business with the damned Navy. They don't know what the hell they want and will drive you up a wall before they break either your heart or a more exposed part of your anatomy."