In the end, BofA may split up Columbia in the hopes that the sum of the parts is worth more than the whole. Good luck with that.
The bottom line here is that these are damaged goods, due in no small measure to the considerable erosion of faith in Bank of America's management. With all the questions surrounding CEO Ken Lewis' handling of the Merrill Lynch takeover and all the hidden costs revealed after the fact, bidders for Columbia are probably a little concerned about what they'll be getting.
You can't really blame them for expecting a discount.