With the seeming collapse of the "Grand Deal" we are left wondering what Obama's true intentions were.
Two theories have been suggested:
Obama was acting as a Master Actor or Obama was a Genuine Compromiser.
With the Master Actor theory, promoted by people like Lawrence O'Donnell, Obama never wanted a deal and essentially pretended to hold talks as long as he did to show himself as a Reasonable Man while still not planning to have a deal on medicare and social security.
This is rather alluring for some because it portrays Obama as a genius politician, gambling and calling the bluff of the Republicans but at the same time (if not only because of political opportunism) secretly protecting America's safety net. It also has the satisfying effect of showing how all the pundits in Washington are wrong and how actual politics works.
However I think, given all the information we currently know, the idea of Obama as a Genuine Compromiser is more accurate even if it assumes Obama to be somewhat politically crazy. If Obama was essentially conspiring to have the talks fail and to show the Republicans up, there would of been leaks and speculation from more than just O'Donnell.
Now we don't know all the details yet, but Obama was probably more "hopeful" (to put it nicely) than he was shrewd.