What is Deutsche Bank Playing At?

I wrote an article recently about banks in Spain and how they have increased margins between the Euribor rate (Base Rate) and the rates quoted for mortgages. So in Valencia yesterday I see that Deutsche Bank is advertising heavily that they will give you a mortgage at Euribor plus 0.27%. What are they playing at and how can they and why do they do it?

I will get back to answer this next week because the answer may well be very interesting.