Let me put it another way with a car analogy. Everyone loves car analogies. Scenario: You want to test how far your car can go at its top speed on a full tank

Let me put it another way with a car analogy. Everyone loves car analogies. Scenario: You want to test how far your car can go at its top speed on a full tank of gas. You're too lazy to actually sit in the car with your foot on the accelerator the entire time so you go and find a brick to lay across the pedal. Unfortunately, when you place the brick across the pedal, you accidentally, unbeknownst to you, deploy the drogue parachute[0]. You walk away, hit the remote start button in your pocket, and the car takes off. RACING RACING RACING, except, you know, parachuted. Actually you don't know. You didn't do it in purpose. You didn't know it deployed. You didn't even see it, because you were walking away. You only found out later when you got back to your car and saw, oh shit, you accidentally deployed the chute. What a boner. Why was the deploy button so close to the accelerator where a carelessly placed brick could bump into it anyway? What a stupid design mistake THAT was. Now. Do you call your test valid? [0] https://en.wikipedia.org/wiki/Drogue_parachute https://en.wikipedia.org/wiki/Drogue_parachute