a) While Congress performed well in Bangalore district and the constituencies in the district, it was the rural areas where Congress lost out on. As you would expect, a whole lot more seats in the legislative assembly come from the Karnataka rural hinterland and not its urban areas. In short, Bangalore does not matter politically in the state.
b) Krishna and Deve Gowda have a legendary rivalry going back more than a decade now and the JDS-Congress government could not have been formed if SMK was nominated as the CM candidate. Deve Gowda needed somebody malleable and ductile to his thinking..and lo! there appeared Dharam Singh.