Unintended consequences of the Mozart Effect

I just rang up my bank to try and blag some (admittedly pretty minor - £25) charges back.

They put me on hold and played Mozart at me for five minutes.

A brief and amicable argument about implications of the outstanding bank charges test case later, they agreed to give me my £25 back. 

Listening to Mozart, according one 1993 study, raises IQ by a shade under 10 points.

What I want to know is - did my bank's inefficiency just help me outwit its staff?

Putting people on hold and playing Mozart at them could turn out quite expensive for banks.