My "How to Get A Pharma Job" category over on the right has taken on a whole new meaning these days, what with me (and all my co-workers) scrambling around for new positions. You run into all kinds of interviewing styles out there, most of them fairly benign - but there are a few techniques that (to me, anyway) are warning signs.
The "Let's Go to the Board" folks can be in this category. (I've spoken about this before). While it's true that you want to make sure that a prospective candidate understands the science of what they're doing, a dissertation-defense blackboard grilling may not be the best way to do that. A medicinal chemists's job does not, to a first approximation, revolve around solving mechanism problems. It's a useful skill, and can be used as a surrogate for general mental acuity, but it's not the absolute first requirement.
At the other end of the scale, you have the HR-department "If you were a tree, what kind of tree would you be?" interviewers. I should point out that the people who ask these sorts of questions generally aren't the shining stars of the HR office themselves. And yes, I actually have heard of someone getting the tree question. I live for the day that someone tries it out on me.
People who have been through a lot of training courses may also try out a technique called "Behavioral Event Interviewing". That's when they ask you about some situation you found yourself it - "Tell me about a time when you had to meet a tight deadline", or the like. There's nothing wrong with this in principle, but if it's the centerpiece of the whole interview process, I think that it turns into a moral hazard for the interviewee. That is, it's an incentive to bring out the makeup crew and the special effects team, for a new, improved, version of the past. Everyone does this to a degree, of course, but the BEI style almost encourages it.
And it should go without saying that if you're treated in a disrespectful manner during an interview, and it seems like part of the company culture rather than the work of a random fool, then you should keep on walking. This is rare, but it happens. I knew an associate a few years ago who got a call for a Saturday morning interview at a small company, which was done by several of the lab heads who sat around eating breakfast in front of her. Do you really want to work for a company that thinks that this is acceptable behavior? Exactly.