I thought that all of the items listed in the article were very important to a successful initial job interview.
I noticed that a couple of people criticized the article for saying that you should stay away from the subject of job advancement. If they read the article more closely they would see that it says to avoid this subject in the initial interview and save it for the second or third job interview. I agree with the article on this point.
I agree with Tony Hopkinson about follow up letters. I have never sent a follow up letter, and I have rarely made a follow up phone call. If I have gotten an interview through a recruiter then I find that the interviewing manager usually talks to the recruiter while I am travelling home. I call the recruiter when I arrive home and they either say that I didn't get the job or that I need to schedule a second interview. So I'm saying that even if the hiring manager takes a long time to fill a job the manager will make a decision about each candidate quickly. I have, therefore, never found follow up communications necessary or even desireable.
I agree with Info-Safety about demeanor. Acting like a know-it-all, or acting like a question that is posed to you is insulting to you, or acting in any way that is disrespectful to the person interviewing you is probably a bad idea. It's one thing to be confident, which is good. It's another thing to be a jackass, which probably should be avoided.
This checklist article would be a good tool for anyone to review before going to an interview.
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