>>My guess is a lot of people who have done significant troubleshooting of some kind have figured this out on their own, or been mentored by someone familiar with it.
>
>While driving the car an odd sound occurs front left. Driver stop, looked around and found one tire flat. Swapped the tire to front right. Drives on. Odd sound now front left - it must be the tire.

In the longer version of the joke, it's the service technicians from DEC and NCR who do this twice, and conclude that the cause must be the tire itself. The guy in the back seat, who wasn't talking until this point, is from IBM and says „you can not be sure it is, until you return the suspect part to its original place and try it there again“.