My finance professor told my class a story about his wife and himself were at a fair and encountered one of those games where you have to guess the number of jelly beans in a jar. His wife has a consulting background while he has a background in finance. She observed the jar, tried counting the number of jelly beans on the bottom and extrapolating an estimate from those values. He, on the other hand, just looked through the first couple of cards others had turned in and picked a number that seemed in line with the estimations of others.

He got closer to the actual value.

The wisdom of crowds approach is alive and well in finance. For better or worse, the wisdom of the crowds approach allows an analysis with much less work than the engineering approach. But more importantly, it serves as a type of defense mechanism to the person making the actual prediction especially if he has no skin in the game. If you're way off, at least you're in good company. Okay for counting jelly beans, but it has a potential of being disastrous in other situations.