The problem IS Eglinton. Eglinton is one open lane in each direction through the densest (and getting denser) part of its length: Laird to Jane! True that Allen wasn't supposed to end at Eglinton, but if Eglinton had at least been widened east and west of the terminus, it would have made a big difference. Or how about 2 left-turn lanes?
Really, many of the bottle-necks in this city are easy fixes: like the short on-ramp, westbound from Jameson onto the Gardiner.
Back to the tunnel idea, what about the toll? It's been done before. Hell, if Europe can punch holes through granite mountains, I am sure we can dig a 6 lane tunnel down to the Gardiner! There was a proposal about 10 years ago to build a tunnel under Humber Bay and the city wouldn't have had to pay a dime. You can only guess where that idea went.
Dragging the 'big dig' into this is silly. They were moving highways, train tracks and building tunnels and bridges under/over rivers! Slightly more involved than a tunnel from Eglinton down to the Gardiner. Besides, I admire the Americans attitude of 'go big or go home.' Maybe we Canadians should get some cajones and start thinking a little bigger, too?
All the suburbs look 'desolate' until the trees grow in. I remember how awful most of Brampton looked 30 years ago, now many of the 'older' parts are quite nice. 6-lane arterial roads should be the norm, not the exception.
Really, the anti-car lobby wants it both ways: they want cozy, quiet neighborhoods, bicycle lanes and scenic avenues, but won't acknowledge that there has to be some areas that give way for traffic flow. Jarvis and University are two good examples. Let Sherbourne, Parliament and Church be all leafy and bicycle-plagued but widen Jarvis! Expand the Gardiner and the DVP, tunnel down from Eglinton on the Allen and maybe some of the neighborhoods will be nicer to live in again.
Or we can all just sit around another 10 years until the Gardiner falls down, then it will cost us billions to revamp it.