I did not think it was an unreasonable question. The article also mentions that quite a few of the people who thought they had this ability were unable to demon

I did not think it was an unreasonable question. The article also mentions that quite a few of the people who thought they had this ability were unable to demonstrate it through this sort of test. As a certain percentage of the population think they have a given disease when they do not, I would not be surprised if a certain percentage, on hearing about tetrachromacy, would think they have it for less than rigorously sound reasons.