The problem is not our parties, but us. A Congress split in three would only promote more deadlock.Among the many lessons of the gratuitous debt crisis one seems obvious: divided government too easily devolves into dysfunctional government. So count me out of efforts to create a strong third party: I suspect that increasing the divisiveness -- splintering Congress into three formal parties instead of two -- would only increase the dysfunction. In fact, we already have, in effect, a third party president, as unresponsive to concerns of the democratic base as much as he's at odds with Republicans; and you might attribute the 2010 right wing take-over of the House, and resultant dysfunction, partly to his failure to articulate and defend Democratic populism. 

Besides, liberals complain repeatedly, we don't quite have a second party. The complaint is hyperbole: there are clear differences between Congressional Democrats and Republicans on economic and social issues. But, like a lot of hyperboles, it's partly true: Democrats have not pursued their policy preferences as doggedly and effectively as Republicans, (which is how we ended up with the Bush/Obama tax cuts and a chasm between rich and poor;) and the parties are generally united in their hostility or indifference to civil liberty and their reflexive support for the national security state.

But perhaps the greatest fallacy of the third party movement is the unspoken, perhaps unacknowledged, underlying assumption that members of a third party would be more informed, intelligent, and rational and less self-interested and demagogic than members of the first and second parties. What if the problem isn't the two party system but the flawed human beings who would also participate, as voters and candidates, in a three party system? What if the problem, in part, is us?