Airse for elbow

In the regular Scottish idiomatic expression, someone doesn't know "their airse from their elbow" refers to incompetence of the highest order.

Socialists know that governments don't run capitalism. Capitalism runs them.

 But decisions of government which affect perceived stability, can send shock-waves through the system, enough for it to start 'corrections' depending upon and sending signals of economic significance.

 This recent Latest E.U. spring forecast must have politicians sharpening knifes to weild on each other in the Brexit pro and anti lobbies..