Well I received more information. Perks of working in NYC, lots of corporate lawyers in every building.

The USPS PCSC formulates what they call "Readership costs". These are all expenses depreciation, and similar items that are directly connected with the production and distribution of the readership content of the periodical for the upcoming fiscal year. Since the unrelated business is ATTACHED to the non-profit arm the PCSC takes into consideration all expenses from both arms of the NFP. Unrelated business is part of the not for profit operation. The unrelated business for tax purposes, has NO attachment with what the USPS decides to do for their discounting bases. These codes are written by lawmakers! Hoss is under the assumption that the AMA takes the laws into their own hand.

Oh and by the way the USPS PCSC has an entire classification of discounts just for this specific category because there are more then 2,000 non for profit entities that receive the exact same discount the AMA garnishes under the same class.