[dragonwriter]

> Is this for real? The solution he proposes is specific to Chess!

Yes, that is, it is precisely addressing the question asked, not some unstated drrff hidden intent.

If the tester wants to test ability to apply a particular paradigm, that paradigm should be part of the explicit question. If you want to use a chess representation as a vehicle for testing OOP skills, than specify that object orientation is a requirement in the question.

Otherwise, you should be judging the interviewee on how well they did on the challenge you actually posed. Otherwise, what you are really judging on is whether OOP is the tool the interviewee reaches for no matter whether it's really appropriate to the problem they are faced with.