But you stated "the current system that funnels government funds into the largely private, for-profit, and grossly inefficient delivery system." Now it seems that the largest government system "is the most efficient insurance system in this country."

Your math seems to be twisted perhaps your analysis is shaded by working backwards from your conclusion that US federal government controlled single-payer is the solution and attempting to make the components fit your preconceived notion.

I would tend to look at the situation directly and notice that the federal government controlled solutions seem to be a significant contributor of higher costs and worse outcomes nationally. 

You seem to have faith that giving the federal government the small remaining percent of national healthcare up to 99% or 100% is a rational conclusion. I do not see any evidence that conclusion is objectively justified by current or past results.