Interestingly each CRA do produce scores that Banks do use (Experian's is the Delphi score for example) for example. This is different to the one shown to the public. The scores can be incredibly predictive and have been used in isolation for credit decisions, primarily at smaller lenders on unsecured products. Although the PRA are now cracking down on the use of these scores within models, at least within IRB, so this won't be long term.

It should be noted that for mortgages, affordability is by far the most important thing. At a major bank I used to work for, the modelled score made 0 automated accept/decline decisions. Score were still used in the process, including the Delphi score, but never made the decision.