Nixon will add something. But he will not be the be all end all - not the great white hope. He will be a freshman. Raw. Decent skills. Not spectacular. He will develop over his career.
From what I READ (I do not have inside info) he did not change his mission plans due to Rose telling him that he was indispensable.
It appears to be more due to this:
He was scheduled to leave for the MTC in August 2014 and return in August 2016. August does not work well if you intend to come back, get in shape, and play. BYU seems to be moving away from redshirting and there is a big scholarship issue looming in the next few years. It was a practical move that helps Dalton develop by playing as a freshman. Hopefully, he has kept in shape. It probably also alleviates the scholarship crunch since he will pay his own way this year and only tie up a scholarship for 3 years when he returns. But, he will play.
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