The bit about preferring hypothetical questions over past achievements in interviews sounds dubious to me. The current practice seems to be "behavioral" questions like "tell me about a time you had to deal with <specific type of problem x>, and how you personally contributed to solving it", the idea apparently being that what someone claims (or imagines) they would do in a given situation is a much weaker indicator of their realistic future behaviour than what they actually did in that situation in the past. In other words, actions speak louder than words. However, this is different than simply letting someone brag in general terms about some project they were a part of - the more specific nature of the questioning allows you to get at what the person's real contribution was.

I haven't seen the actual research though (I think behavioral interviewing at least claims to be based on research evidence).