Dear Interviewer,
I truly appreciate your asking me to interview in person. It was exciting to have the opportunity. The six phone calls leading up to the in-person made me think I was vetted and that it was down to culture fit. Your in-person was five hours long, and you took the opportunity to quiz me in-person on some technical trivia it took me literally 5 minutes to look up after the fact and which you did not hint at being critical for the job. Thanks again. I love spending one of my precious few vacation days to go to your offices and see how life could be had you only quizzed me on trivia I happened to have at the tip of my tongue.
Best regards,
Rejected Candidate