I would love to see the source data for that pie graph, or exactly what sort of "analysis" they performed to come up with that. It looks more like something the author simply pulled out of his ass.
Brilliant, I love the way you phrased that.

I've only read a bit of the article myself at the moment, so can't answer the question right now.
I don't really notice any microstutter on my 2x 4870x2 setup and it's just as smooth as any single-GPU system I've ever seen. Then again their results don't show much microstutter on triple or quad GPU setups either.
You won't notice microstutter if your rig can render without any dropped frames and vsync is on, regardless of the refresh rate of your monitor.
From what I can tell, you get microstuttering with single cards too, when the system can't maintain the framerate. Basically, you get an uneven, jerky mess, as each frame takes a different time to render as the scene changes. Perhaps the exact way it looks on screen is subtly different, but I'm not sure.
Where's the poll option for those who use CrossFire and don't get microstuttering? Or, at least an I don't care because I find this poll unbalanced option?
The article is graphics card brand agnostic, hence the poll doesn't refer to particular brands. Anyway, the microstutter problem is only there when the system can't keep up with the monitor refresh, as I explained above.