Or it will but not at 4k. Since the GPUs etc aren't 4k in the iMac.
Is this really the case? How can a GPU drive multiple Thunderbolt displays with ease but not a single 4K display?
I need to read more about this to understand it better. But my impression was that the issue was the bandwidth restriction of Thunderbolt v.1, not a lack of GPU power. If my understanding is correct, I wonder if something akin to a "dual link" connection involving both Thunderbolt ports connected to a single 4K screen would be possible?