Unfortunately, most job applicants are made to feel nervous and even unworthy when they turn up for an interview, so I strongly believe that the first objective is to get the conversation back onto an even keel.
I find that, personally, making the interviewee a cup of coffee, pouring them a glass of water and encouraging a little light-hearted banter also ensures the conversation is more relaxed and productive.
The fact is, the person applying for a position is looking to commit almost half their waking hours to a new employer, and it is my view that many bosses don’t consider the enormity of this when they are talking to new applicants.
If we really want to see the “real person” it is critical that we spend time up front to help them relax and to reinforce to them how much you appreciate them considering you as their new employer.
This approach will usually also bring out aspects of the person's personality that may have otherwise remained subdued, and which could have affected the outcome positively or negatively.
Of course, the decision of whether or not a person is successful will always remain with the employer, but the one-way interview approach is outmoded, often ineffective, and could even be interpreted as disrespectful.
Just as job applicants should ensure their interview skills are up to scratch and they prepare well, so too should we employers.