Javaness2 said:
The EGD is not allowed to accept games played with more than 9 handicap stones for rating purposes.
On the other hand, tournaments can run with whatever komi they like, even systems such as auction komi are valid.
I do not think this is true. When you submit a tournament to EGD you need to specify a tag ;HA[hN]. N can range from 0 to 9. The system will then deduce a handicap for the game based on the
grade-difference between the players. However if N=9 and if you specify explicit handicaps in the games then your handicaps are taken as is. So you could enter a handicap of as many stones as you like. See for example
http://www.europeangodatabase.eu/EGD/To ... y=T191117E. In the UK we regularly use a combination of 9 stones and komi with 15 points per handicap stone above 9. The system does not record the komi.
I think a handicap rule based on grade-difference is wrong. In all McMahon rules I have ever seen, the handicap is based on the current difference in McMahon score (with some possible reduction). This handicap could be a lot different to the one based on grade-difference, and is more in keeping with the McMahon spirit of trying to give all players fair games.