It looks like it isn't going to happen:
Dear Mr. Cooper:
Thank you for your suggestion for the intersection of 22nd Avenue NW and NW Market Street. You requested that we change the operation of the traffic signal to include an All-Way Walk (AWW) phase.
The AWW operation is used sparingly throughout Seattle, as it causes delay for all users of the intersection, including pedestrians. The operation is most beneficial when high levels of pedestrian activities are present as well as similar high vehicle volumes, particularly conflicting turn movements.
This particular intersection would not be a good candidate for the AWW operation due to the adjacent intersection of Leary Way. This extra "leg" of the intersection creates a crossing distance too long to be served within a signal cycle.
If you'd like to discuss this in greater detail, please feel free to contact me directly at (206) 684-8086 or email@example.com. I will be happy to assist you further.
Senior Traffic Signal Engineer
Seattle Department of Transportation