Because they now have the role of market maker of last resort, central banks should become much more active in ensuring that any asset permitted to be classed as capital by a bank can be liquidated on demand in a public market.
If this is so, then they must needs take a view on the value of all sorts of assets and therefore of all sorts of capital investment. This brings us back to a point I was making earlier on – whether the independent central bank is a valid institutional model any more.