Excellence in Government "Logic"

Apparently, a great justification for Medicare part D (prescription drug coverage) is that spending $55 billion annually has saved about $12 billion in hospital stays.

Forget Aristotle's categories ("barbara, celerent, darii, ferio, camestres, cesare...."), can someone teach DC bureaucrats and the "researchers" at Mathematica/Harvard the definition of "savings"?  I'm pretty sure spending $43 billion more annually does not count as one.