[travisjungroth]

> What's the likelihood they've all standardized on the exact same default heuristic?

In some cases really high. Professionals are often under the same constraints, have no reason to be diverge, and even are incentivized to converge in opinions. These are not independent probabilistic events.

To my earlier example, _many_ appraisers adopted the heuristic of “appraisal = offer + irrelevant_random_noise”.

You security guard example doesn’t really apply to professional opinions. They’re usually done independently. By hiring multiple security guards, you’re forcing them (or at least encouraging them) to spread out. Sure, you’d get a similar effect if you hired ten doctors to spend 20 minutes with you all at the same time. They couldn’t all listen to your heart and tell you to take an aspirin. But if you visit them one at a time they can. So it’s more like ten security guards all watching one camera feed from different rooms.

Examples of this problem aren’t made up. Citigroup accidentally sent $900 million dollars to creditors. An issue I believe is still in litigation about a year later and has been a huge loss. It was approved by three people.