What do you think about the idea that central banks will just buy their own bonds with freshly printed currency, to prevent bond yields spiking?

It's been noted that many foreigners have been selling US treasuries, for example (the Chinese, the Saudis), but yet the interest rate doesn't seem to reflect this. Who's buying these bonds? I suppose it must be the Fed quietly buying them.

If rates did spike, would this spell doom for pension funds, and all the debtors of the world, like government? It seems to me there is a motive to control these markets. And if this is the case, then they are just pushing the default onto the currency, and risking the market rejecting the currency. Or am I mad?

Anyway, great post, as usual.