Should he commit, I think the only thing that keeps Newton from being the clear cut starter going into Game 1 next year is another laptop incident. For every bit that Relf tops Tyson Lee in athletic ability, Newton can match that on top of Relf - and Relf certainly isn't any slouch in that department.
If Russell feels compelled to transfer next year if Newton commits, so be it. I would think it would be a mistake however. He'd only get one more year of playing time assuming he went somewhere he knew he could start immediately - so you can rule out a high-profile transfer. It'd have to be a lateral move program-wise. I think it would be in his best interest to sit tight, learn from Mullen, learn the system, and be ready to go when his time comes. That is, assuming he's bought into the system. I can only think that is the case, otherwise he would have not committed to playing under Mullen if he didn't think the system could benefit him or he couldn't excel in it. If he's as talented as most say he is, everything will work out fine for him down the line.
All that being said, expect Newton to sign, Russell transfer, Newton get arrested, and us be left with Relf and the walkon to back him up next year. <span style="font-style: italic;">That</span> would be the MSU way.