Hi Emlyn,
A hedge is essentially taken to protect against market risk. Deposits rates on the other hand are not really mkt rissk but determined by the management of a bank based on various facters such as theeir liquidity, asset growth plans, cbr rate etc.
An interest rate swap will be used to hedge against adverse movement in a mkt traded benchmark such as libor. Some facilities / bonds issued at libor + spread will be at the mercies of libor movements (for a moment ignoring the manipulation scandal for sm london banks), should such a rate rise in future.
So essentiialy it boils down to: will u take A swap to hedge against a management decision or market risk (which the bank wont have control). Thats why it may not apply in the scenario u describe