I'm not entirely sure what you are saying here, Kirby. I suspect that may be because you omitted the important word "historically" from the quote, and so may be talking about something different from me.Going "overboard in investing in thickness" is a "risk-based strategy", because it means you are playing too slowly, thereby increasing the chances of losing the game. If it's an issue of komi, strategy should adapt to play well according to the rules of the game. On the flip side, if a particular strategy increases the overall win rate of a given pro, there is evidence that that strategy was less risk-based. Professionals are in the business of consistently winning games, and a strategy that is consistent with that is not a risky one.
We can easily surmise that ever since go became popular, it was populated mainly by people who saw it as a form of gambling. There is certainly enough evidence of this in recent centuries. The point is important because in gambling go it is not simply victory that matters, but the size of the victory. The prize is the number of silver taels you collected.
But when it came to prestige as the prize, a pro mindset developed in which simple victory, and then the total number of victories, was all that mattered. Life then resembled the two main styles of go - dour, long-term investment (thickness) with slow rewards over the thrill of spectacularly kills balanced by spectacular losses.
In Japan the dour style became favoured for various reasons. One was that face was important. A go master could make a living by securing patronage, but he had to be sure he didn't upset the patron. Small victories or even small, engineered losses against said patron became the safest mindset. This was reflected in modern times by the well known story of Go Seigen terrifying his fellow pros when he first played warlord Duan Qirui and demolished him. But this was not unique to China. Segoe Kensaku, in his autobiography, mentions the need for prudence in playing with Duan even before the Go Seigen incident, and remarks that this was just like playing the politicians and peers in Japan. He specifically says it was about face.
In the days of Sansa and the shoguns it may have been more about the whole head rather than just face, of course! Shoguns and daimyos avoided loss of face by not having their games recorded, or by avoiding playing the pros - just watching. But this crystallised into an effective prohibition of Japanese pros playing gambling go at all, or anything that looked like it. This wasn't restricted to go. the whole ethos of Edo life was about control, hence avoidance of risk. So the Shogun kept the daimyos clustered round the foot of Edo Castle for much of their lives, where he could keep an eye on them. Art forms such as No acting, linked poetry, flower arranging an the tea ceremony were all straitjacketed into rather rigid forms bounded by rules and made-up traditions. Even in the economy this applied. Merchants - the world's most notorious risk takers - saw fit in Japan to aim for modest wealth, to avoid sumptuary laws and expropriations. The wisest way to make money was to follow the candlestick theory of stock markets and to aim for small, consistent and relatively consistent gains. It is no accident that the favoured style of Japanese pro go uses the stock-market term souba as a description for good go.
This mindset permeated the professional ranks of all walks of life. At the lower, amateur levels, of course, chaos, speculation and just having a good time breaking the rules (e.g. kyogen, festivals, gambling go) all flourished. But what was esteemed, and ultimately led to greater fame and material profit, was professional mastery.
What distinguished professional mastery was not eliminating the risk of losing, as such. That is impossible anyway. Once you embark on a game of go, there is close to 100% risk of one side losing. Rather, the go and shogi professionals aimed to reduce the risk of uncertainty (or of disorder in other, similarly complex fields), and thereby reach a state where things became clear enough for a human to understand what is going on. At that point, they believed that with their superior training could kick in and they could "read" their way to victory, irrespective of the margin. In many cases, this amounted to a heavy reliance on boundary-play skills, a reliance which was reinforced in two major ways. One was the lack of komi, which increased the safety margin for those who relied just on winning irrespective of how much (even in the early Edo days there was an understanding that first move was worth around five points). The other was the effective absence of time limits, which allowed deep, deep reading.
Both these conditions (no komi, long time limits) persisted in Japan until modern times. The Oteai (and its equivalent in Korea) enforced no komi until close to the end of the 20th century. Hence we may assume that the traditional style of play was still in favour. Indeed, we can see this in small but insignificant sidelight ways. The self-written potted biographies that used to be included in Kido yearbooks usually included a description of go style. There were some brave souls who described themselves as fighters, but the majority would label their style as "orthodox" and no-one ever saw the need to explain that that meant solid, thickness-based play. Similarly, women's pro go was looked down on because it was mostly fighting go. This contempt was nothing like Nigel Short's contempt for the female chess brain. It was more that female go pros were relatively weak and so had not yet reached the most desirable level of "orthodox" go.
A similar state seems to have obtained in Chinese go, although with an entirely different background. There as no government patronage. Rather, patronage came from civil servants, often corrupt, for example Salt Commissioners diverting the gabelle to their own pockets rather than the Emperor's coffers, and rich merchants allowed to speculate and take risks (foreign trade included, unlike in Japan). In what might be considered the heyday of Chinese go, lavish go parties were held on the Yangzhou painted boats and masters were put up in rich men's villas. Yet even in this ambience, it seems that the best masters evolved a mindset that favoured simple victories over big victories, even though gambling go was rife. Given the absence of formal organisation of go in old China, hard data is lacking, but we can make inferences in various ways. For example, games records often would not give the size of victory (and they did, it was apparently to emphasise the closeness of a result). There are anecdotes about rich patrons trying to tempt masters into spectacular play by offering extra taels for capturing groups. And when masters passed their peaks, they would turn to writing books rather than hustling amateurs.
A safe style of achieving victory was thus favoured in old Chinese pro go as it was in old Japanese pro go, but it didn't have the same external reinforcing tendencies as in Japan, and so an argument can be made that old Chinese go began to fall behind Japan in the late Qing. This was less to do with relative skill and more to do with a deterioration in the economy, but it does seem that the masters who managed to survive (such as Zhou Xiaosong and, later, Wang Yunfeng did sill cleave to the "simple victory not size of victory" style of play.
Professional go did not exist in Korea until very modern times, so bangneki gambling go was almost always the dominant form. Indeed, it became a problem for the authorities more than once in South America when migrant Koreans took their "bad" go habits with them. But within Korea, fighting go was not looked down on. It might even be said to have been favoured. Japanese style go dominated the peaks of pro go in Korea for a long time, because the likes of Kim In, Cho Nam-ch'eol and Cho Hun-hyeon had studied in Japan. Yi Ch'ang-ho studied in Korea, but under Cho Hun-hyeon, and of course there as also the example of Korea's own Cho Chikun (and Ryu Shikun) in Japan. But fighting go, risking uncertainty, was always bubbling just below the surface, and was popular with fans. For these, Seo Pong-su, admired for having acquired his high level without studying in Japan, was the archetypal Korean pro. Yi Se-tol became another glowing example later.
Even without the presence of Yi Ch'ang-ho, it would be rash to say that it was simply the fighting skills of Yi Se-tol and his peers that brought Korean go to the top of the go mountain. It was probably more to do with the go environment they worked in. They had fewer sponsors, fewer games, and there was increasing pressure to lower time limits to make go more marketable for sponsors. We cannot discount the desire to knock Japan and its surrogates in Korean off their pedestals, either. We all know the result. More fighting games, which terrified the Bejasus out of Japanese pros, games ending in resignations more often than in endgames. Possibly for psychological reasons as much as skill factors, Koreans began to prove stronger. But skill factors cannot be discounted. Japanese pros had developed a bad habit of their own. Far too many spent the bulk of their time on the opening (an over-obsession with thick play), and while their reading skills in the middle game were clearly very good, they just as clearly weren't as sharp as those of the Koreans.
The Chinese, meanwhile, were watching form the sidelines, and analysed the Korean success. They concluded that the Japanese souba style had had its day and they copied the Koreans (and favourably re-evaluated the old Chinese masters along the way, looking at then through the prism of the modern Sino-Korean style rather than the Japanese style).
Again, we have all seen the results, but now AI is changing the environment. Indeed, we might argue that we have seen the long evolution of pro go encapsulated into the few years that AI go has been around. At one point, when Monte Carlo algorithms were all the rage, programs would sacrifice points just to get down to the ultimate simple victory of half a point. Programs like katago have moved on beyond that, and while they don't obsess with size of victory (as far as I know) they don't mind the odd big win.
I suppose it would be of some scientific interest to look at gambling go in AI terms, though. If size of victory is the criterion, would go change a lot? I mean how much would it change the style of play if the measure of success was to, say, lose 8 games by 1 point and win only 2 games by 5 points each.
There are quite a few arguable points in what I said above, but I think I have said enough to show that the word "historically" was important. I also think that the word "uncertainty" needs to be borne in mind constantly when we consider the relationship between strategy and tactics.
