If an airline believes in overselling a plane (i.e. the money generated outweighs the ill well cost when things go wrong) even a 50 seat RJ, and that same airline has a 50 seat business cabin, it would stand to logic that they would oversell the business cabin. Either the costs outweigh the risks, or they don't. Be it on a $200 ticket or a $3000 ticketm the exact same economics go into play, and a larger scale per passenger on the business class side. The advatages ate 15x greater than Y, and the risks are equally 15x greater.

It would be inconsistant (and business should not be inconsistant, it should follow a well though out plan based on statistical evidence) to say that doing one is beneficial while doing the other is not.

That would be like a blackjack player in LAS playing "by the book" on all of his $5.00 bets, and then when he bets $1000 and the house is showing a ten and the player has 15, having the player stand instead of hit. The costs should not dictate the practice, only the statistics. (unless of course you have the oportunity to surrender and the deck is 10 rich, in which case a different variable has been introduced.)