(a) One of my suggestions was to petition "Harvard to add an off street bike path parallel to Shepard St to accommodate those cyclists" which wouldn't require city tax dollars.

(b) To be a little Socratic and re-frame your question back to you, (b.1) why should motor vehicles have so much road space? (b.2) And why should so much of that road space be designated for the storage of privately owned vehicles? I.e., why is parking needed there? Cambridge is a city with transit and all those houses on that street have driveways (aka off-street parking).

(c) Why are my city tax dollars going to subsidize motor vehicle users so they can drive around threatening the lives of pedestrians and cyclists and generally be entitled?

Fair enough about the amount of traffic on each street, but drivers speeding is also a problem that needs to be addressed. And it sounds like those cyclists need to be accommodated, not excluded

If there is that much demand, then maybe you should petition the City to find a way to add a counterflow bikelane to Shepard St or petition Harvard to add an off street bike path parallel to Shepard St to accomidate those cyclists.

Knowing what I do of the area and looking at some streetview references, I'm pretty sure I would be much more comfortable riding against the flow of traffic on Shepard than I would riding with the flow on Walker St (especially with the travel lane being fenced in on both sides by parking lanes)

There may be less traffic in Sterling, but they are all doing 50 mph around blind corners with no shoulders. Cycling would be much risker