Is Biden's Partitioning Proposal a Plan for Peace in Iraq?

Senator Joe Biden, Democrat from Delaware, is pushing a new peace plan for Iraq, a variant on the partitioning idea that I mentioned here in early August. Under Biden's plan, a partitioned Iraq would function as a federation of sectarian states, rather than as three separate nations, the aim of most previous partition proposals.
But Biden's plan doesn't address the key problem with splintering ideas that has been the sticking-point in previous proposals. A Kurdish nation could be broken off today with very little problem. But, in spite of sectarian violence that has created hundreds of thousands internal refugees in Iraq, the Sunni and Shiite populations and their property are intermingled. Sorting all of that out would be, if not impossible, nearly so.
I don't have answers...and wouldn't offer them if I thought I did. But it will be interesting to see if Biden's plan gets legs as he campaigns for the presidency.