When the Gardiner Expressway is closed for repairs or resurfacing, the additional deverted traffic ends up on LakeShore and Queensway. Even with the extra traffic on the Queensway, the streetcars are not blocked. Eglinton would be same, since the LRV's will be segregated from the automobiles in the open sections.
The following photos are from an inspection of the Queensway (then called Queen Street) right-of-way on July 18, 1957:
Interesting that this right-of-way was built not just because of the Gardiner construction which forced the streetcars off the LakeShore, but also in anticipation of a Queen Street Subway from Roncesvalles eastward. The Queen Street Subway would
not have used
heavy rail, but
light rail (or streetcars) despite the name. The original Queen Street Subway had PCC cars in their drawings of the line. The Queen Subway wasn't built however, so the right-of-way was orphaned, as it were. If the Queensway right-of-way was built today, there would be protests because High Park lost the strip of land and water from the railway north for the Queensway roadway.
After saying all that, Eglinton
will be a subway. Maybe not heavy rail, but a subway none the less. It will however use light rail, similar to the original designs of the Queen Street Subway, but with newer LRV's.