Again, this prediction is worthless if Bush does not do well early and gets out of the race.
There's a lot you can say about Romney, but his is incredibly intelligent, and a highly successful business man. For sure he rationalizes that all he needs to do is rack up huge blue and purple states like NY, CA, IL, and WI. If he does that, and guys like Cruz and Paul split places like TX and KY (Bush likely wins FL, btw) it really won't matter how much we hate him. We'll be stuck with him. Again.
What part of "He [Mittens] would eliminate Jeb and Rubio (who inherited some of his key staff members), so let him run." did you not understand?