It's not what you know, but where you went to school. Or so believe MBA students at top-ranked business schools Chicago, Wharton, Stanford, and Harvard, where students have in recent years adopted policies that prevent them or their schools from revealing grades to potential employers. By doing so, they hope to create a less pressured environment and remove some of the risk from taking difficult electives.

During the dot-com boom, when lucrative job offers for MBAs were abundant, grades, it seemed, were largely beside the point. After all, when valedictorians and slackers alike shared in the bounty, the varying benefits afforded by an A-plus or a B-minus were negligible. But in today's hotly competitive job market, such differences loom large. Nonetheless, the nondisclosure policies have been passed down from year to year, with each new class viewing this radio silence on grades as its academic birthright.

The MBA experience is all about preparing for life in business. But grade nondisclosure eliminates three defining features of the business world: risk-taking, accountability, and often ruthless competition. By removing grades from the B-school equation, the students are doing themselves a huge disservice -- creating the illusion of a noncompetitive world that will be shattered upon graduation when they will find themselves poked, measured, and prodded like everyone else.

The irony is that these men and women will, as managers, be required to take others to task for their actions, doling out pay raises and promotions based on measurable performance. Maybe accountability is a lesson they should learn right now.

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