>>"Given that even the proponents of MMT don't agree on what it is [..]"

I'm not an economist but I have read a lot of the MMT literature, including the available textbook (1) and it's a totally coherent framework.

Can you point me to some of those contradictions that you have observed?

(1) - https://www.amazon.com/Macroeconomics-William-Mitchell/dp/11...

It's clear actually, that the US must increase spending, increase taxes. You spend to get out of recession, or you cut and make it worse, as has been demonstrated in every recession since records began. The failure to spend has brought us to a double-dip. For some grounding in economics, try the following: http://www.amazon.com/Macroeconomics-N-Gregory-Mankiw/dp/071....

Update: For a more specific analysis of an analogous situation - the Japanese "lost decade", try: http://www.amazon.com/Holy-Grail-Macroeconomics-Revised-Rece...