Sounds like a pretty successful bidirectional filter to me. (As in: you apparently don't want engineers who don't know this detail, and I wouldn't want to work at a company where that kind of trivia is a litmus test.)
It's not trivia. If someone doesn't know the difference, they're going to allow bad data into our database. Large webapps with poor model validations are security and maintenance nightmare.
Actually, I am reminded of an error that happened which was similar to this. After I left a past company, an engineer flubbed a validation which allowed a subtle bug to go undetected for 10 days which cost the company $500,000.
No, money wasn't being stolen, but the validation error meant that clients' money was being spent and not being tracked. The company had to eat the costs.
