Canary Wharf is a bit of a trick question, because it has no curvature and the angle at the top means it either wouldn't fit at all, or the point would hit the bottom of the groove, or if it fitted perfectly you couldn't tell where the contact locations would be.....
But the Gherkin, is another matter ! I mean, really this just can't be a coincidence :
It's a markup showing how the very tip of the Gherkin would fit in a groove to scale. C'mon, these things don't happen by chance, someone has found the instructions we sent into space on how to build a record player, and has just got the scale a bit wrong
Contact locations are always exactly where the tangent is 45 deg, BTW.