ajldub makes some good points. The main one is the limited growth potential in the Glebe. Only a Bank Street subway line could reignite it as a major growth corridor, in spite of the rigid objections of cranky Glebites. If the Glebe wanted to grow more it would have to "grow offshoots", maybe aong Catherine toward the Canal (there is a new seniors condo complex there, facing the Queensway - I guess the hard-of-hearing seniors aren't affected by the noise?), and maybe the half-blocks from Bank on either side could have more restaurants or minor retail, as in Fourth Ave. east of Bank. The Lansdowne frontage is an enormous opportunity but it has its limits too.
Both streets offer "extended linearity" that crosses several neighbourhoods - the Glebe is just one of them along Bank and it is hard to visualize extensive redevelopment (I can, but most Glebites probably can't, or won't). For instance, setting aside the obvious former KFC, take the LCBO lot - next to the park, etc. Prime site for a condo. Could easily be 6 storeys. The block with the Beer Store and the Mister Muffler, same thing. But there are many difficult sites - such as the small parking lot north of the Indian restaurant, itself a strip mall, next to the Bose store. Former gas station. Very small site, expensive clean-up - how many storeys would you need for something to happen there - 6, 7, ... 12? Horrors. And yet... should it stay a parking lot forever?