First of all, I want to express my sincere compliments to the nice community of Twixt players in Japan. As far as I can understand from the online translator, they are very active in many aspects of Twixt, such as the set up of variants of the game and new handicapping methods.
Probably they do not know that Alex Randolph, the author of Twixt, spent almost 6 years in Japan, from 1966 to 1972. In those years, Alex studied Shogi with some of the best Shogi players of that period. He would have been proud to see the nowadays interest of his favourite game in Japan.

From the files published by the Japan Twixt Association, I read about the Card Twixt (see the other topic) and about a couple of handicapping methods.
Among them, the first one is that the pie rule is not allowed.
The second one is to allow to the less rated player to occupy some fixed points, such as e5 and other points, symmetric with respect to e5.
This handicapping method resembles the Go handicapping, in which it is conceded to the less rated player to occupy some fixed “handicapping points” with his stones.
Later, on the topic of this forum “Row handicapping”, started from David Bush in the 8th of June of 2021, I was informed that there are some more handicapping methods among the Japanese friends.

I am quoting:

“They also had an interesting system for handicaps. Players are ranked in “classes”, and winning against someone from an above class without handicap brings you up to theirs. Winning five games in a row in your current class also promotes to the next one. Playing a handicapped game between classes is based on (roughly) the following rules:

• 1 class difference: the stronger player can't swap first move or form an unconnected “kosumi” (1-1) between their pegs

• 2 class difference: in addition, the stronger player may not form an unconnected 4-1 or 5-2 relation between their pegs

• 3 class difference: in addition, the stronger player may not form an unconnected 3-1 or 4-0 relation

• 4 class difference: in addition, the stronger player may not form an unconnected 3-3 or 4-4 relation”

I am not sure of having understood everything about the prohibition of forming certain connections between pegs. Do these rules indicate that the stronger player cannot use the cited configurations for the whole game? It looks like a boxer that is fighting with only one hand? (and I apologise for this brutal oversimplification).
If so, these handicapping methods resemble the many attempts that have been performed during the years to balance the Go-moku game (five-in-a-row game, to explain better) until the definition of the rules of Renju (in which the first moving player, that has a consistent advantage, cannot reproduce certain configuration for the whole game).
I am interested in receiving more information about these points. Thank you.

I don't know much about these handicapping methods either, But perhaps user mmKALLL would be more knowledgeable about it. Unfortunately for us, he is very busy. I agree that they are like how white is handicapped during play in Renju.

Thanks for the information. I did not realize Mr. Randolph studied Shogi or that he was in Japan for so long.

Speaking of the growing contingent of Japanese players, there will be another real time event on Boardspace, Saturday the 13th of November, starting at 10:30 pm Tokyo time and lasting perhaps 3 hours. There will be at most 3 rounds with a time control of 20 minutes per game with 20 seconds increment added to your time with each move you make. Without the players from Japan, this new tradition would never have started in the first place.

Hello. Let me reply as one of the Japanese players.
I think one of the major factors supporting this Japanese community is yukiblue. He has trained a lot of Japanese players. In fact, I am one of them. One of the great things about him is that he has trained many people who have no (or almost no) experience in abstract games. Also, he thought of handicaps too.
This may not be the purpose of the topic, but I want you to know that yukiblue is a part of the community.

Just a brief clarification, but this system is generally only used when introducing beginner players to the game. It is somewhat analogous to “Atari Go”, a variant of Go where the first one to capture wins the game. Some teachers gradually change the win condition of Atari Go to “first one to capture three stones”, “first one to capture five”, and so on until the student realizes that the game is virtually identical to regular Go.

Similarly, yukiblue and some other players came up with this system of “classes”, to help new players ease into the game. Generally the stronger player has a severe handicap, with the goal of helping players find answers to one type of threat at a time. I would say that the system has been quite successful, as a lot of players have been able to learn the game's basics before having to deal with complicated tactical scenarios. Even people who have not been into abstract games have been willing to learn Twixt in depth. However as galispiar mentioned, much thanks also go to yukiblue's perseverance during the past two years, building the community from three people to almost 30.

To borrow your example, it can indeed be thought to be similar to boxing with only one hand. Games between experienced players practically always use the swap rule, or occasionally the stronger player may allow the other to play first move without swap. I have also tried to introduce row handicapping, but it has received a mixed response so far. The Tokyo community is (hopefully) still in its early stages, so there will no doubt be more experimentation needed to find the things that help bring players to the game.

When we are talking about Japan community, do you mean it's a community everywhere in Japan and so that is mainly on the internet or is it let say in Tokyo and people are playing real time together in a deticated place or something?

These handicap rules are interesting. I think one of the main motivations for handicapping is to ensure that the game remains sufficiently challenging for both players. However, in most games (Shogi, Go, etc), the handicaps only change the starting configuration, and it doesn’t actually change the tactical gameplay.

I don’t know if I like that idea as a handicap because it feels like it doesn’t train you for the real game, but I love it as its own variant. Imagine some kind of asymmetry where each player has a different set of restricted moves. It’s probably very difficult to balance, but it will certainly be quite an experience if it works.