Asking an obvious question and expecting a different type of answer. Just read what he posted.

"Describe how you would program an elevator.

I spent the good part of an hour verbalizing how to do this, only to have him point out the flaws in every idea I had. As I answered each of his points, he found something else wrong.

He didn't care how I would program an elevator. "

If he really didn't care how he would program an elevator, he should not have ask the question. The question is deceptive and designed to trick the interviewee. Trick questions in a interview are strictly forbidden in working environments governed by EOE. If the interviewer actually would have told him that (which I am not sure he did)then the interviewee could have grounds for a lawsuit. Particularly if the interviewee was a minority. It's not the first itmie this has happened, believe me..:-D