Every year they state the over 1,000+ new animations that were added to make the gameplay smoother and more realistic. So they would have to throw all of these animations out and just start over? Look at NBA2k, Madden, NHL and FIFA, they have all updated the player models and continue to use legacy animations from the previous gen consoles.
I would welcome some insight from someone with programming experience. I just can't believe that every animation would need to be redone.

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