And as a dev team we'd rather do formation subs than mascot mode. However, mascot mode was such a minute change that it had no real impact on our schedule. It was less than a day worth of work.
Formation subs on the other hand is something like 300-500 hours of dev time. A significant impact. Trust me, we wanted to do formation subs... but one of the most difficult parts of our job is making hard cuts to our task list for the year.