Why is 30hz a limitation for video? Most video is 24 or 30fps, so 30hz should be fine, no? I can see 30hz being a limitation for gaming but you wouldn't be able to get good fps at 4K resolution anyway. So basically you should be able to run this at 4K all the time.
I haven't seen it in person - one of the downsides of being in rural New Zealand is no friends with cool toys :) - but I've seen much less severe problems on paper be quite nasty.
In game development, my day job, the industry has recently been cracking down on micro stutter, where even randomly skipped single frames at 60fps can destroy the appearance of smoothness.
I see what you mean. Doesn't the HDMI standard have a way to fix this? It could just have a mode where you have 30 frames per second sent to the screen with the indication of which 60hz or even 120hz timeslot to use them in. It might need a little more/faster memory in the screen but should work fine.
http://www.anandtech.com/show/7436/nvidias-gsync-attempting-...