Of digging holes and filling them in again.

Did Keynes really say that?  Here's an article that strongly suggests that he did.  This is the thinking that motivates Krugman and his ilk.  Better than nothing!, they say.  Because that is what Keynes says.  If you are going to spend money, do something useful with it, like produces goods for some purpose.  Digging holes and filling them up again improves nothing.  You can do the same thing by merely giving the money away.