Walkie Talkie architect 'didn't realise it was going to be so hot' (2013)

Combining glass and curves has been rare because it's technically difficult to build large curved glass. They were hardly ever combined until 1850, and it's still difficult today, 170 years after Crystal Palace. It's done though.

Buildings go through review, which is rather like code review, and the review finds problems, and some slip through. In the case of this building the architect ordered a second review, where the bug was spotted and its consequences computed and found to be acceptable. (This is something engineers do all the time. When I had a hole made in a wall at home, a structural engineer computed how much the floor would sag and found it to be acceptable.)

I'm guessing that the second review was carried out precisely because the architect wanted to be careful about those curved surfaces.

Of course you can pretend that the curves were built in order to focus light and blame people for it. In that case you should accept that people blame you, too.

That one person does intent and another computes effect is deliberate. A kind of four-eyes principle. Then more eyes look at it when the plans are submitted to the city's authority, but that isn't usually as thorough as the review cycle between architect and hired engineers.

In this case they computed that the peak heat would be 36°C, the actual peak afterwards is given as 72°C. Those are very different temperatures.

FWIW, based on my somewhat primitive knowledge of this (I didn't finish that school) the most likely cause for the difference is imperfect modelling of the wind. How buildings affect wind is still an active area of research. Both this building and its neighbour affect air circulation in ways that couldn't be modelled using the current state of the art. When focused sunlight works on calm air, it can raise the temperature a great deal. Warm air staying calm instead of rising is a surprise, of course.

(The poor modelling is common BTW, although usually not that serious. In my native Norway snow drifts often collect in surprising spots around new buildings, because the building produces calm air here, wind there.)