I agree that there are some people that need interview prep and some people that do not need it. I have several clients that I do not even suggest interview prep to, as I know they will do fine in the interview. Other clients just need a little polishing of their answers. I have yet to encounter anyone in aviation that is a complete lost cause. If someone is getting interview prep and sounding like a robot, then I sincerely wonder who is doing their interview prep.
Interview prep is not about "fooling" the interviewers. It is about telling your own story, in a succinct, yet understandable manner, avoiding comments that will get you backed into a corner. It is also about understanding how your answers will be viewed by the people sitting on the other side of the table - a side of the table I sat on for six years at two different companies.
SWA hires for many things, including judgment, leadership, teamwork, etc. Their system is copyrighted specifically to their culture and mission. They want to know if you are going to fit into their culture. Not every person has every quality for SWA, and anything you learn from prep can be used at virtually any other company, as about 98% of major corporations (inside and outside of aviation) conduct behavioral-based interviewing.
I interact with Human Resource and Recruiting professionals on a consistent basis. I do this so I can keep a pulse on the hiring process. I learn on a continual basis - even after being in the employment consulting business for almost 19 years.
If you prep with a spouse or significant other, that is helpful, however, unless they are trained in interviewing techniques or the relationship is strong enough to survive criticism, I would be careful. Find a friend or family member that conducts interviewing and prep with them instead.
Be careful about video taping your interview prep (professional or otherwise). It depends on the kind of person you are - will you be constantly obsessing during the interview about your personal quirks, or will you be cognitively aware of them. Know who you are as a person and make your decision from there.
There are plenty of people on this board that do a fine job with interview prep. If you choose to prep, find someone who is reputable and knows how the process works.
Just my opinions on the topic...
