I agree: he blew it. I think interviewers let their guards down, becoming casual and conversational in interviews when they already decided the candidate is not going to work out. The interviewers presumably feel good that they let a candidate leave on a high note (i.e.--"at least I didn't put him through the ringer")...and the candidate never gets a clue, whistling all the way home, like a moth to a flame...
OK, so it seems the kid may have perception issues, and none of these hard core uber experienced Recruiting professionals believe he did actually blitzed the interview.
Can we give people tips as to what would be a sign that the little fella had actually blitzed the interview?
a) a Contract on the table to sign before he leaves the office.
b) a tour of the office is normally a good sign