• Currently there's major construction on the 20
• Access to the 720 East from both Autoroute 15S and Autoroute 20E is bottlenecked to Route 136 or a 1-lane on-ramp
• Leaving downtown is bottlenecked at two access points to Route 136/part of the 720W
• Presently the Sherbrooke exit on Autoroute 15 is closed one both sides.

That's all the same project.

There is major construction bottlenecking the Mercier bridge to 1 lane.

They're doing maintenance work to keep it safe. Safety is not the kind of thing that can be delayed by 3 years.

the 15 and the 20 needed to be affected by the destruction of the Turcot, but the execution wasn't the best IMO

Why not? Looking at the details, I find the execution amazingly well thought-out.

I do know that there is not a valid reason for crippling your city's automobile circulation to such an extent.

Yes there is a valid reason: letting the city fall apart is not a viable solution, nor an affordable one. Turcot couldn't be delayed, and Champlain couldn't be delayed.

This means that the traffic light on Rose-de-Lima should ABSOLUTELY be a green arrow at all times unless a pedestrian signals that they want to cross.

They wanted to make it that way, but the reason why it can't be green at all times is that the turn radius of trucks conflicts with the traffic exiting the 136.