I gotta admit

[Spike89]

10. Well, he's gotta clean up the primary mess

I don't think Mitt is stupid, and despite his incredibly tin ear most of the time, I think he may be learning a bit. If he were to move to the left at this point, he'd gain nothing (the middle/independent segment probably doesn't start paying attention until just before the conventions). However, he does have plenty to lose by reinforcing the far-right's distrust. He's got to do everything he can at this point to reassure the rabid idiots that he isn't going to reasonable.
By August, you'll see him subtly shifted to a right leaning moderate, hopefully (from his perspective) it will be a smooth move that doesn't cause the freepers to actively campaign against him. I do expect he'll try and stake out a few key topics on the far right that he can hold onto and point to. In other words, he may become even more insanely hawkish on Iran, while quietly trying to get the whole slate of women's issues the republicans are getting killed on to fall into the background. On the other hand, he may decide to double down on the culture war stuff and "soften" on the war stuff.
Mitt is flexible, mainly because it is easy to bend when you don't have a spine.