I'm a one on O, two on D. You can have a lot of different variations of each formation. So you can run the Pro-Set for example and have like 5-6 variations (Like have RBs block and TE go out for passes, TE & one FB/RB stay in to block, everyone go out to catch, or max protection where only WRs go out, etc) making it like 6 formations. So you can practice 15-20 minutes on the Pro-Set.