This design looks like you could get more than one roof segment involved, too, especially if there's a lot of traffic. I didn't know that they actually manage spacial relationships like that, but I guess it makes sense. I suppose that's why the extra antennas on some models.

In theory, a radio reflection off something non-flat can be a treated a bit like an extra point source. My curved tea kettle won't mess with wi-fi, because a reflection off it just looks like a straight but lossy path that's the sum of the distances involved. If something's a wavelength across weirder things can happen, of course, but wi-fi is in relatively short bands for the most part, and there's more than one so it can just switch if it's in a dead spot. A wi-fi signal will also be modulated pretty fast, though, so now you have to think in frequency space as well, I'm not sure how that works.

Google's hipster building is on a scale that's very different from a kettle, but at least as complex geometrically, so maybe that's where the gap in access point design lies. They expect small distortions and big perfect reflections.