It's happened before. Custom stadium sounds were supposed to be in Madden 10, and so were sideline catches. They didn't make it in Madden 10, but showed up in Madden 11. Online franchise, which was server based, was supposed to get contracts and salary caps, well...nothing happened in Madden 10, or Madden 11.
Remember how the ratings were supposed to be stretched out to separate the elite player from the average one ? To this day punters and kickers can hold their own on the oline, and QBs can play in the secondary.