AppId is over the quotaAppId is over the quota By Martin de Sa'PintoZURICH | Fri Oct 7, 2011 10:26am BST ZURICH (Reuters) - Stiff competition for top private bankers has kept a floor under pay even as low interest rates, flaccid client trading and tougher regulation squeeze industry profit margins.Sky-high pay and bonuses for investment bank counterparts may once have turned private bankers green with envy.But the drive to slash wage bills and rein in risk has made investment bankers expendable as many banks realign their business around more stable private banking."Pay was never extreme in private...