Northern Rock call it Rate for Risk - in their eyes (and I agree with them), it is better to offer the customer something than to decline them. Then it's up to the customer to decide. Altough the rate may have moved slightly, the paymen ts shouldn't have moved that much. You could aways try another low rate loan, but many of them use very similar scorecards and you may end up with exactly the same rate.
As a note, all banks and building societies are bound by advertising rules which state that 66% must be offered the TYPICAL rate advertised.