And do you know how many cars continue down south on Dufferin? You obviously have no idea how bad Dufferin St traffic is, I also read somewhere not that long ago of Byford mentioning another north South subway down Dufferin St.
Lots of discussion here of downtown and the west side, which surely have many worth projects (I look forward to Church being pushed south).
But on the east side the 2 I find most irksome are Don Mills to Coxwell (these should be the same road); hugely expensive bridge w/some eco-issues as well) however, the benefit would be the removal of Don Mills from the valley and creating a logical corridor for buses, cyclists, pedestrians and cars.
Currently, if you lived at say Coxwell/Danforth and want to end up at Don Mills/Lawrence, you need to (by car), make the jog on Coxwell over to Don Mills, and the circuitous run through the valley not bad, not great. But as a transit user, you have to go all the way west to Pape in order to get the Don Mills Bus, or east to Victoria Park, up the take a bus going west, truly inconvenient.
Also, there are no sidewalks on the current Don Mills and the route into the valley and across is not winter-maintained, so you face almost as circuitous a route as a pedestrian to go north.
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The other one I'd highlight is the Lawrence east gap; of course due to the area, this is less likely to be changed; and I wouldn't want to see a link here make a mess of he York U, Glendon campus; but the Post Rd jog is not only silly, the effect of having transit (mostly) divert around the area, and it and traffic joining Eglinton doesn't serve the City well. Though at least their is some transit through the area, so its not as cut-off from the City as it might be.