The point of the coding interview is whatever the interviewer thinks it is. Sure, it SHOULD be to see if you are a good person to work with, but that's not always the case, if the interviewer thinks that you should produce a working and optimal solution(for whatever reason), that's what you will be judge on. Unfortunately not everyone uses the tools at their disposal in the best way. And it might not even be a case of intentionally doing it wrong, it might be that the interviewer doesn't know any better. If you take an experienced dev and you put him to make interviews he will not always know the best practices to interview someone.

For Google that simply isn't true. Check out Work Rules some time. Google has put a ton of effort in having a repeatable hiring process that specifically avoids this problem of interviewer bias. Most people, even Googlers do not really understand their hiring process and how it works. It isn't to hire the best coders.

I agree with you. I put more the emphasis on the optimality of the solutions because that was the feedback from the recruiter. During the interviews, I made sure to talk through the problems indeed. That is a whole skill in itself.

It sounds then like the interviewer ought to help solve the problem if engaged properly then. I would pull on then if stuck anyway haha.

I concur with this. You might be best coder/analyst/techie in the universe, but it is impossible to work with you, then you are useless.

Your interface with the machine is only a part of the equation, and your interface with the team is so important.