And as I suggested later in that thread, one way to make it feasible to share the sidewalk space (i.e., everything off to the side of the road) is to make the pedestrian and cyclist portions grade-separated, with the cycle track lower than the pedestrian portion. This would still require bike signals at intersections, not to mention reconfiguring intersections.
And I agree with you 100%. We merely have a difference in semantics. I wouldn't call grade-separated paths with reconfigured intersections "sharing sidewalk space", I would call it "high quality cycling infrastructure" or "exactly what we should be doing right now". Saying "sharing sidewalk space" just encourages the government to widen a sidewalk, paint a line down the middle and then go about telling everyone what an awesome job they've done for cyclists even though all that's changed is that it is now legal to cycle on unsafe infrastructure.
The fundamental difference is in level of design. When we're going about building separate paths and reconfiguring intersections, we will inevitably be designing to accommodate the differences between cyclists and pedestrians (much higher momentum, higher speed, more space required, less capable of dealing with poor surfaces). "Sharing sidewalks", on the other hand, implies not really considering their needs at all, but simply telling them to "go ride over there with the pedestrians".
My point is that there are literally hundreds of kilometres of sidewalk outside of the core that are rarely if EVER used by pedestrians as most people are driving rather than walking. Take Victoria Park ave for example. You could go from Steeles right down to the beaches in the middle of summer and maybe barely see a person every few kilometres. Seriously outside of the core with few exceptions most sidewalks are empty almost all the time so why not better utilize them?
Like I said, we shouldn't just start riding all over them because we would get hit by turning automobiles. As mentioned above, we should indeed be "better utilizing" the space beside the road, but we first need to make it safe for cyclists to use. This is called building cycle infrastructure, and there is no magic solution that will instantly do it for low cost, because it requires design and construction.
That said, you are definitely right that since there are so few pedestrians in many parts of the suburbs, our default roadside infrastructure should be bicycle paths, rather than sidewalks. This is what they do in the Netherlands. In built up areas where there are pedestrians, there are always separate bicycle and pedestrian paths. But once you start reaching the edge of the city, the sidewalks end, and the (rare) pedestrians walk on the bike path. Note that it's not that "cyclists ride on the sidewalk".
If you implement a few rules with sharing the sidewalk/bike lane with pedestrians (ie have a bell to alert pedestrians of your approach and to slow down when passing etc) then you could easily make much greater use of current sidewalks by turning them into dual use bike lanes/sidewalks.
We already have these rules about how to ride on multi use trails, but they aren't the ones that really work in practice. Riding on multi use trails in Toronto's suburbs, I find that as long as there are very few pedestrians and everyone acts as they would on a two lane rural highway, everything works beautifully. Walk or cycle on the right, and wait for a gap to pass in the oncoming lane. No need for bells or slowing down. But as PinkLucy mentioned, this completely falls apart once there is anything higher than a low density of pedestrians, and by the time you reach the density of the MGT, it's a complete fiasco. The solution isn't telling people what to do, it's to design infrastructure which inherently causes people to act in a way that works.
For example, rather than telling the cyclists to slow down and the pedestrians to be more alert, we should build separate paths for each so that cyclists can speed and pedestrians can relax.
EDIT: You might also want to check out the
City's webpage about why sidewalk cycling is illegal.
