It isn't a useful heuristic at all. The vast majority of people can't program. If you take a random person from the population I'm going to assume that they can

It isn't a useful heuristic at all. The vast majority of people can't program. If you take a random person from the population I'm going to assume that they cannot program. If we are talking about 'from the population of programmers' I'd wager (a large sum) there are more men who claim they can program, but actually cannot, just given the fact that the field of programming is a male dominated industry.