This is a good article that uses the Golden State Warriors as a case study on the power of positionless basketball. With the right five players, the argument about size at the post is almost moot. Of course, no team--college or NBA--has the players the Warriors have, but this article captures the essence of where BU plans to take the Illini.
http://basketball.realgm.com/article/239916/The-Epitome-Of-Positionless-Basketball
When the Warriors are playing five-out basketball, they have plus defenders at four of the five spots on the floor and versatile offensive players at all five. They are playing the maximum amount of speed on defense and they are playing in the maximum amount of space on offense. The dilemma it poses is two-fold - it’s almost impossible to counter that style of basketball in the modern NBA and no one can play it as well as the Warriors can.
http://basketball.realgm.com/article/239916/The-Epitome-Of-Positionless-Basketball