One of the interesting things about motion capture technology is kind of how it's all put together. The idea is to make it as much a "normal" acting experience as possible and then being able to do all these amazing technical things with it afterwards.
Before, they had never found themselves broken together. Usually, it was one needing the other but not both needing each other, and so there had been a way, by touching, to borrow from the stronger one's strength.