I've experienced the same thing while conducting interviews. The flip side is that some people have great answers and they often open up and show their passion

I've experienced the same thing while conducting interviews. The flip side is that some people have great answers and they often open up and show their passion for programming when they get to talk about the things that interest them and aren't as focused on how nervous they are trying to answer your question correctly. I've also has people tell me that they read the study guides for the Microsoft certification exams. I'm not trying to start an argument about the value of certifications. I think it is questionable though when asked how someone keeps up with the latest technology, they reply that they read books with content of questionable real world application, from a single company, that are updated every three or four years.