Somehow I doubt that they can't figure a solution out (in the networking sense). You could have 4-5 nodes spread all around the world, in pretty well connected data centers, to send you everything you need in a few seconds at most - or do it through elsewhere.
A few seconds is a huge deal. The block time is 600 seconds. Three extra seconds by itself means 1/2% extra loss. As TPTB said, they may be concerned about small costs, but this isn't even that small as mining goes. Miners frequently optimize for less.
If the chinese miner has a good electric bill advantage, good equipment, the ability to mine 0-tx blocks (to gain a broadcast advantage / fast propagation compared to others who transmit a few mb worth of blocks) and he only gets delayed a bit when receiving large solved blocks by others (if he is not doing network work-arounds), I think he still has the edge.
Why do you think it is binary, or that China's advantage is necessarily so durable? Competing miners outside of China also have good electric bill advantages, have good equipment (arguably Bitfury's equipment is better at the moment), could also mine 0-tx blocks if they wanted to, etc.
The one thing that is absolutely unique to China is the GFW. It makes no sense to assume that the unique properties of the GFW don't factor in Chinese miners' thinking here. Hearn was just stating the obvious.