In real-world Finance, they don't pay for elegance. They pay for power - predictive power.
Robert HaugenCAPM also makes use of what is called a "definitional identity." This is something that is automatically true, simply because of the way things have been defined.
Robert HaugenSo you see, in the end, it is nearly certain that the power of prediction must triumph over the arrogance of elegance.
Robert Haugen