I'm really intrigued by how such rooftop bank signage became a phenomenon going into the 1960s (also cf. the TD at the NE corner in the earlier photo)--esp. since prior to that time, decorum seemed to dictate against such aggressive financial-services advertising/signage (instead, you had rooftop advertising for more profane stuff like food and automobile products).
Dunno where else CIBC roof signs of that scale existed in Toronto--though there were more modest versions, like atop the IOOF building at Yonge + College. (And I remember a few of those TD orb-in-a-flowerpot signs: Vic Park + O'Connor, Bloor & Jane, etc)
