Sure, it can be fun to ask “What song best describes your work ethic?” or “What do you think about when you’re alone in your car?”—both real interview questions from other companies—but the point is to identify the best person for the job, not to indulge yourself by asking questions that trigger your biases (“OMG! I think about the same things in the car!”) and don’t have a proven link to getting the job done.

A common theme: it’s not the fancy-schmancy thing that brings us what we need. It’s the boring, mundane thing.

For example, the US Department of Veterans Affairs has a site with almost a hundred sample questions at www.va.gov/pbi/questions.asp.

And to be fair, we have moved from a philosophy of hiring exclusively generalists to a more refined approach, where we look across our portfolio of talent and ensure we have the right balance of generalists and experts. One of the luxuries of scale is that you can build areas of deep specialization, but even in those pockets we monitor to make sure there is always an influx of fresh, nonexpert thinking.

Ryan Tate of Wired wrote the best summary of it I’ve seen: Here is what [20 percent time] is not: A fully fleshed corporate program with its own written policy, detailed guidelines, and manager. No one gets a “20 percent time” packet at orientation, or pushed into distracting themselves with a side project. Twenty percent time has always operated on a somewhat ad hoc basis, providing an outlet for the company’s brightest, most restless, and most persistent employees—for people determined to see an idea through to completion…