Right now with the delegate count, Romney is playing a disciplined and smart campaign for himself, ammassing over 50% of the delegates with just 40% of the vote. the two of them together (Newt and Rick) could stop that if they come together and one of them steps back for the betterment of the country.
My critique of your analysis is that, unfortunately, not enough of the Gingrich/Santorum voting bloc would remain intact in that eventuality. After either Gingrich or Santorum dropped out, sufficient numbers of their bloc would migrate into Romney's camp to put him at or above the 50% level for the remainder of the primary contests, ultimately securing Mitt the nomination.
We really needed someone like Sarah Palin to step up in 2012. In retrospect, I believe she really missed an opportunity, although I also think she may very well have another opportunity in 2016, regardless of whether Romney or 0bama wins the general election.
And Perry probably should have stuck it out for a while longer. He might have been able to recover.
I really feel sorry for Newt, who I believe is the only announced candidate who could have decisively dominated 0bama both ideologically and intellectually in the general election debates.
I continue to have significant reservations about Santorum, and sincerely and honestly believe that he is "not ready for prime time", and while I would support his candidacy if he were to be nominated, I don't think he could win the general election if put to that ultimate test.
Romney is, of course, simply abysmal, and unlikely to energize conservatives enough to defeat the incumbent, even though 0bama is quite weak.