Eh, I disagree. A good interviewer can dig into past experiences and pretty quickly get a sense of a candidate. Interviewing is a skill that can be acquired and developed.

Problem is, the skills you need to be a good interviewer don't necessarily overlap so well with the skill set of a good software engineer. It's much easier to get people to ask about what they know, irrespective of whether or not that will be an accurate indicator of technical skill.