Long-run strategies are a human crutch. It's easiest to see when you solved a game mathematically, that you can just value positions independently.
Go hasn't been solved to that level, but it's apparently been solved to higher level than humans ever reached.
I am just parroting http://www.uschess.org/content/view/12677/763 here, so I might as well quote:
"To catch an alleged cheater, Regan takes a set of chess positions played by a single player—ideally 200 or more but his analysis can work with as few as 20—and treats each position like a question on a multiple-choice exam. The score on this exam translates to an Elo rating, a score Regan calls an Intrinsic Performance Rating (IPR)."
This approach also allows to score historic players absolutely, instead of only relatively and trying to find sets of overlapping lifetimes until we reach the modern age.
