steveintoronto
Superstar
Time will tell! It is certainly a huge improvement in the sense of openness, but the light level depicted in the drawing is that of direct sunlight at noontime, note various nuances, including reflections. Any natural light will be lateral, not overhead. Of course, renderings are always complementary that way, in practice, unless very intense artificial light is used above, the sense will still be that you are below ground, albeit in a cavernous space.What an incredible improvement over the stuffy low ceiling concourse. I almost want to cry.
I just realized from that depiction what it is that's so amazing about Grand Central, and many other classic railway stations, (Toronto Union's Grand Hall is still this): No support columns! That being said, the treatment afforded to the ones shown is effective in not hiding them, as that would be impossible, but making them minimally intrusive visually.
I'm still having trouble visualizing the walkway as described and as depicted on the floor diagram http://urbantoronto.ca/forum/attachments/digdown-jpg.85250/
The diagram indicates a width of the walkway as being 1/3 that of the moat. The rendering alludes to much less, and perhaps is taking licence with the sense of space that the depiction portrays.
I'd be very interested in seeing the architect's detail drawings of the walkway, from both vertical and lateral aspects.