That said, I'm sure Reader has several features one could do without
But I find it quite misleading to talk about framerate capping. As a simple cap wouldn't guarantee that you present your frames in sync with your screen. So you might get 60fps but still with tearing.
And in a scenario as you describe it, I guess the smartest move would be to lower any graphics setting only slightly and then run on full fps in sync. But I guess that's what the people who suffer from the overheating issue should have done in the first place.
Btw, your render times are off by a factor of 10.
However, VSync is disabled by default in SC2. And this might cause the issue.
A: "What iPhone do you have?"
B: "Oh, I have the Apple one."
Also, "high speed" is kind of a debatable term in this context. I guess 2MB/s is a high speed (I hardly ever get beyond that). But downloading a game from my library still takes longer than installing it from a disc. And the connection issues are even worse for the dedicated servers I run. Installing/updating server installations have always suffered from low speeds for me. This can be very frustrating at times.
I still agree that Steam is most likely the best platform of it's kind around and I appreciate a lot of the benefits compared to retail games. Yet the above mentioned experiences leave at least a bitter aftertaste.