Mathematicians' invasion of economics is complete, sad but true
Why sad? Evolution.
The problem is that, theories are getting more and more esoteric with every passing day and this mathematicians turned economists are building most complex models with assumptions far removed from reality...
Keynes was a mathematician, but he rarely used mathematics in his papers ( but o'course it was loong ago)..
I do not have any problem against usage of maths in economics, actually maths makes things simpler ( I still remember how difficult undergrad level economics books in economics because they rarely use calculus and spend two pages explaining things and doing no good job of it, which can be taken care by simple differential equations)..
But problem starts when it is only mathematics with little economics
Once I read an interview of Clower, where he said now the field is full with applied maths guys who find it difficult to contribute to theoratical maths so shift to economics.