Wells Fargo is terrific to work with. However, you will need an agent/broker to expedite a short sale option.
The most important and profound aspect of a short sale package is the home owner's financial information. The bank is less concerned about the hardship letter and other "filler" information associated with the package. I think there are rules and "ratios" that vary from bank to bank. The bank is aware of various scenarios that include foreclosure, REO and short sale options related to each property in its inventory. If their ratios (probably computer generated) show it is more profitable to let a home go into foreclosure then I do not think there is much an agent/broker or other representative can do to prevent this from happening.
My problem with the short sale process is how the banks seem to be removing the "human" element and possibly relying on computer generated information as a primary tool to approve short sale options. This may, in part, explain why the process may drag on for months with little to no response from the bank.