actually the story is detrimental to helping people understand how technical systems and troubleshooting work, because it's so poorly invented.
lots of people, both technical professionals, and non-engineers who are observant and have an appropriate level of belief in causality, troubleshoot transient failures like this all the time. a difference in the amount of time between shutting down the engine and starting it up is one of the first things that someone like this would test, or control for. it's beyond implausible that the second time the guy got vanilla (after riding along for 4 trips, two long and two short), the engineer didn't raise the question of how long he was in the store.
people troubleshoot things like this by being able to separate causes which are plausible, although unlikely and surprising, from things which aren't remotely plausible. the 500-mile email story and the stories above about sunlight interfering with sensors demonstrate this.
if you're the sort of person who believes that the type of ice cream you get might affecting your car's ignition - the type of person who buys ice cream often but never thinks about how long the errand takes, you simply never get the point of being able to make a pattern between those two things. the second time your car doesn't start, you blame it on the scratch-off lottery ticket you won $2 on which used up your supply of luck for the day. the third time, you conclude that the car ignition knew you were late and likes to choose its failures to cause maximum annoyance. and the fourth time, you realize that your mother-in-law gave your car the evil eye that morning.
the story as told, especially when presented as a real parable about engineering rather than an amusing myth, is frankly insulting to the other type of person. the untrained, not necessarily educated person who cares about machines and believes in material reality. the person who starts checking their watch each time they go to the store and a couple of weeks later is telling their mechanic friend "if it's more than 3 minutes or so, it's fine. but if you try and start it before 2 minutes, then you have to wait another 5 before it's ready to go".