No idea why.....

We've never considered Front Office Football for a sim for our BSB leagues. It's good stuff, and it has a college version too (although it's mostly about recruiting and player management, from what I can tell). I own FOF 2004 (although 2007 is the newest version, and the only one easily available for purchase) and the college version (The College Years), and they can interact with each other, with draft classes from college going to the pros. It's very deep, and quite fun. 

The downside is that the leagues are fixed at a certain number of teams, that being 32. That said, the AI seems to be decent, so open teams wouldn't kill us. It's something to chew on the off-chance that the new software doesn't make it off the drawing board (although I have the ultimate faith that it will).