I'm with UD on this, mostly.
There is Value Engineering at play on the CityPlace buildings, as there is everywhere, including at Peter Street Condos. The question is what degree of value is being sought, or at what cost to the developer do compromises regarding the final look stop being accepted.
NBGtect: Of course the architects must be concerned with a budget all the way through, but the concept design progresses long before the budget is finalized, and long before every component of the building is costed. I know of projects in this city where everything has been specced, the units are sold, and as the working drawings are about the get underway the developer has come back to the architects and said "I need it for $3 less per square foot".
In this case, RAW's colour concept for the exteriors here would have been formulated before every detail of the mullions were determined. If you look at the renderings more closely, yes, you will see all of the mullions there, but they tread more lightly on the design scheme as shown than they have proven to do on the finished exterior. It can be partly chalked up to their width, and to a greater degree to their colour; the brightness of the white certainly makes them stand out more than they do in the renderings.
You're right that the appearance will change with the colour of sky that the windows are reflecting, and the amount and the direction of light at the particular time of day the pics were taken. This time next year the building will have a lot of white blinds behind the window glass too, so the lived-in look will change it again. It's a lot of subtle strokes that add up to a perceptibly different final look and feel.
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