I estimate that our current autoscore is already correct 99% of the time if the borders are closed, just based on my own experience with it. And mine seems to handle any actual failing cases just fine so it could be an order of magnitude better. But I haven’t played around with different rulesets or really tried to break it much.
Here, maybe this will be a controversial case:
Autoscore v3 marks both bottom groups dead - since if White plays first, the lower-left one dies, and if Black plays first, the lower-right one dies. Without any unquestionably live black stones in those corners, it can find no justification for keeping the groups alive.
But in a real game, if the players passed, of course they didn’t see the weaknesses, right? A while ago I brought up an almost identical position here (that original one actually turns out to work fine) and everyone but me thought the groups should be scored as alive.
It seems hard to “fix” this kind of situation - a 1 in 10,000 kind of game - and I’m skeptical that it’s even clear what “correct” would be in this case. Or if you make a clear rule that covers this case, it’s probably going to break some other weird 1 in 10,000 kind of situation in a bad way.