Such as not considering that payouts would be phased in, such as they were for TCU and WVU. Additionally, the Big 12 is getting so much in NCAA credits because most of those credits were earned while the Big 12 was a 12 team conference -- that number will slowly go down. If you bring in two schools that have good basketball, as well as football, the NCAA credits will actually be better. Again, remember that the current NCAA credits would not be shared with the new schools, only credits earned after these schools joined.
He also doesn't really factor in the huge boost for a conference championship game. Apparently Jerry Jones has offered big money if the Big 12 will play the game in AT&T Stadium -- that between the game receipts and TV rights, some estimate it would make $40 million alone for the Big 12.