If someone mentioned it in the context of "below" average, I would initially assume that they had used Median (as it is a measure of central tendency). Having said that, I would seek clarification as to the basis used for making the claim.So if someone said "50 per cent of Australians are of below average intelligence. That's just maths.", you would instantly know they are talking about "median"? How exactly?
The point I am trying to make is, there are different types of averages, a fact people here are trying to argue against.
Stats can say whatever you want them to say. A level of critical thinking always needs to be applied.