>The best interview process I've ever been a part of involved pair programming with the person for a couple hours... You never failed to know within a few minutes whether the person could do the job

There is something funny about the "best interview process" taking "a couple hours" despite giving you the answer "within a few minutes". Seems like even the best process is a little broken.

Lightly ironic indeed! Though I’m not sure “broken” is exactly the word I’d choose.

I can only speak for myself, but I imagine myself as a candidate approaching a “couple of hours” project or relationship differently than I would a “few minutes” speed round. For that matter I can think of people I know professionally who I only know through their behavior “on stage” in structured and stylized meetings of a half hour or an hour—and I don’t feel like I have any sense at all of how they would be as day-to-day coworkers.

If we sat down to work together, you’d probably have a sense in the first few minutes of whether or not we were going to work out—but that would be contingent on us going into it with the attitude that we were working together as colleagues toward a goal.

That's mainly because there were multiple pairing sessions, and even if you knew the person was going to pass, there are still a couple more people who need to meet them, and a schedule to make sure they're available to do that. Plus due diligence, etc.

Nor am I saying it was a perfect system, just the best I've seen in terms of results.