If I recall correctly, some similar (ridiculous) regulations are preventing the resurrection of the original roof at the Gladstone as well. Zeidler's daughter actually expressed interest in rebuilding the old roof, but hasn't been allowed thus far.
Sometimes the ham-fisted bylaws in this city are absolutely infuriating. Though, did the people behind this reno even want to restore the old mansard? Something inside me says that bottom-line motives were provided a sigh of relief in knowing that the most financially significant piece of the reno couldn't be achieved.