I don't quite follow all of this, as I'm pretty ignorant of how central banks actually function, and also there are some graphs in it; my brain shuts down as soon as it sees a graph.

The take-home message though seems to be this: there are three superficially distinct ways in which a government could finance investment to kick-start an economy in times of depression, recession, or "liquidity trap". You can use Plain Vanilla Deficits (PVD - spending more money than you take in because you're the government and you can), Overt Monetary Financing of Government (OMFG - getting the reserve bank to give you the money before you spend it, because you're the government, etc.), or People's Quantitative Easing (PQE as proposed by Corbyn - getting the reserve bank to give money to a new National Investment Bank, which will fund your worthy causes, because yada, yada). The practical differences all seem to come down to precisely who it is that signs their name on the "give me money, please" chitty, and how many carbon copies you need. Presumably, among better informed people than myself, one of these options looks more politically acceptable than the others, which will all turn your hair instantly white with shock.

Where any of these differs from "traditional" Bernanke-style Quantitative Easing, is that QE just has the reserve bank standing out on the street corner shouting "Free money! Get yer free money over here! Great big wads of it!" to passing private investors. When these investors don't want to sink any money into anything productive because they're terrified that, for instance, the other post-2007 shoe is about to drop, they won't take the money at any price, and you've achieved nothing. Worse, what money you have managed to offload has probably gone into unproductive rent-seeking and/or speculative activity by people wealthy enough to handle the losses of playing in the casino economy. Thinking that some sort of democratic process could possibly reach a consensus on useful ("shovel-ready") public projects to finance (by putting a positive number on one side of a balance sheet and an equivalent negative value on the other side) may sound wildly radical, but it beats investing in a dole queue.

More at NEF: "The Bank of England’s own research indicates that just 5% of households own 40% of the assets boosted [by 2009-2012 QE]. QE became a way to shovel more wealth into the hands of the already wealthy."

And here's Simon Wren-Lewis on Central Bank Independence and MMT: "A National Investment Bank can be set up perfectly well based on borrowing from the market, and you can ensure it gets the funds it needs by a government guarantee. The only reason you would avoid trying to do that is because the NIB debt would count as part of the government’s deficit, and you were worried about the size of the deficit. The last people who should be worried in this way are followers of MMT. " Yes, but politics. I think there's something to be said for having a clear public distinction between consumption and investment, even if in reality it's a purely a matter of accounting.