What do you expect from a new hire? What kind of time to productivity curve do you have in mind? I think all 4 forms of interviewing you are suggesting are rea

What do you expect from a new hire? What kind of time to productivity curve do you have in mind? I think all 4 forms of interviewing you are suggesting are reasonable and whether or not they are demeaning for the interviewee depends mostly on the attitudes of those involved. If the interviewer is a jerk setting out to dominate the interviewee, and does not even bother to conceal how they think the interview is going, it's going to be a demeaning experience. If the interviewer is polite, empathetic to the interviewee, and probes without hinting at the opinion they are forming, even a terrible candidate should be able to leave without feeling like they were unfairly treated.