KataGo is a lot stronger than pros, but it still doesn't know how to play go optimally.
I agree with the gist of your wider comments, but I think we can go even a bit further, in particular with the above statement.
I would suggest that this could be rephrased as "AI is more successful than pros." Not stronger, because when we say someone is strong we tend to be implying they know a lot about the game. Cho Chikun is VERY strong but is not specially successful at the moment.
I would go further then and say that bots are more successful mainly because they don't get tired or lose concentration or feel pressure or get bad habits. Were a human able to eliminate all these frailties, I think we would find that they are very, very close to the bots. I say this partly because I've been watching various grandmasters commenting on the Tata Chess Tournament. I was struck by the fact that they now rarely mention "the engines" and, when they do, they are often dismissive of them (e.g. even the engines can't play this endgame properly without a huge amount of time). I've already mentioned here that we are seeing something similar in pro go. There was a Big 7 title match recently (Kisei Game 2) which had a long commentary. AI was mentioned just once, and that was to check correct play in a tricky capturing race (and the pro play was confirmed as correct). What I sense is that pros have long got over their initial AI shock and are now feeling more assertive and confident about their own views and knowledge. If that is justified, and I think it is, we are justified in still cleaving to what they tell us.
I think there is a simple but telling experiment that should convince doubters. I'm sure most people have even tried it already. Play a bot and get creamed. Then play a bot but after every stupid move by you, take your move back and try another. By "stupid" I mean a move where, as soon as the bot plays you realise instantly that you fell into a hole because e.g. you carelessly filled in a liberty. You were careless, not ignorant. You know the tesuji but you didn't look. You played like a typical human. And when you take back your moves and play more carefully, you will suddenly discover that you are maybe four or five stones stronger.
Go further and imagine that you had an app that flashes up the value of every boundary play on the board (2 points gote here, 5 points reverse sente there, and so on). You KNOW how to count these positions, but in practice you can't be bothered with all that fiddly stuff, so you play by guessing. But of the values were displayed, you could probably play a very decent endgame. Accepting Rin Kaiho's argument that amateurs lose abut 30-40 points in the endgame, you would find that you've suddenly become 2 to 3 stones stronger -
with no extra knowledge.
This is not so strange. After all, top tennis players hire teams of people to help them prepare. These people are not as good at hitting the ball as the player, so can't really teach the player anything about the mechanics of tennis. They are there to provide motivation, detect bad habits, plan tactics, keep the player fit, relaxed etc etc.
Go pros don't have this support, except in China for international events. Amateurs don't have it and have to make do and mend. I believe go (and chess) amateurs who study with bots, who devise ways of counting thickness, who memorise josekis or even whole games, or who cuddle their cats or do Pilates while they sit at the go board are all, in a sense, chasing fool's gold. At least when they tell themselves things like "I'm now stronger because bot X shows me my main mistakes." That is not to say that I think such effort is wasted. Far from it. It's just that I think the cause-and-effect is not what they think it is. I believe the true cause of any improvement is simply more time spent at the go board. Whatever floats your boat to make you spend that time is good for you, as an individual. Other people probably need different motivations. Some people told they need more exercise may simply buy a treadmill. Others may buy the latest Nike trainers, which makes them go to the gym so they can be seen with their new bling. Once there they go on the gym's treadmill. Some may get even swankier and hire personal trainer at the gym. They all get fitter. They may feel it's their new shoes or the hunky personal trainer that made the difference, but in each case it's the time on the treadmill that deserves the credit.
Do bots help go players with motivation? My impression is that they may help pros, because they make very few mistakes and these can be pinpointed by the bot. The task of rectifying the mistake is then doable. But amateurs make lots of mistakes and so are overwhelmed by the bots. I remain to be convinced that having a bot point out you made a 10-point mistake is of any real value, when each of the previous ten moves you made all made a 1.5 point loss. The real task you face, both as a pro and an amateur, is to work out WHY you make mistakes, not WHAT the mistakes are, because the odds are that you already have knowledge of the WHAT (in the game I referenced above, Ichiriki said straight after the game something like "I know I made a lot of mistakes in the endgame" - he didn't need a bot to tell him that). Bots are incapable of telling you WHY you made a mistake. Unfortunately it seems that humans are likewise not very good at telling you as an individual WHY
you make mistakes. It may be for entirely non-go reasons. E.g. you are unfit and so can't concentrate for long periods.
One reason I deplore the lack of discussion and anonymity on L19 is that go is by and large a solitary activity at the best of times. In the modern age, with people playing in front of computers instead of people, and hiding behind handles and avatars, they are becoming more and more like those people what just watch porn in their hotel room when they travel. It really is a lot more fun to get out and mix with the locals. And finding out what makes the local people tick is actually a better way to true knowledge than listening to a guide who tells you this cathedral was built in 1573. That's because, if you understand how other people tick, you are more likely to realise what will make you tick. Ergo, people are better for you than bots (or tour guides).
