We're both in agreement that canadian byoyomi is the worst system. But Japanese byoyomi seems to me more suited to the game of go than bonus time. The reason for this is that with bonus time there is some incentive to compete for who can move the quickest (Oddly enough, bonus time has the most dynamic features and is best able to adapt to the time needs of the individual move, but it still results in a discrepancy between the times available to the two players). The advantage of Japanese byoyomi is that players have the luxury of thinking about moves other than the current one during their byoyomi. With bonus time, the amount of time available to each player is always a significant aspect of the game. With Japanese byoyomi, this aspect of the game is reduced in importance. Hence, since each player is likely to undervalue how much time they have in their own minds, even a liberal alotment of time will result in the player with less time remaining feeling a little disadvantaged, and playing quicker to catch up. Then it is quite likely that the fastest player to make his move will set the pace. with byoyomi, you have a certain amount of time to make each move, and if you use less than that you have the remaining time to think about various strategies that are possible on the board in various places, leading to a very interesting game. I do not say that bonus time is bad for go "per se", I just say that, given the particular properties of go, it is slightly less good than Japanese go. These properties are

1) There is a large but unknown number of moves in the game. 2) The game is extremely "deep" in terms of its complexity.

However, for some games I believe a great compromise is possible: use main-time + bonus time in place of "main-time", and use byoyomi when that runs out. The idea would be to minimize the perception that either player is ever "assed-out" time wise. But for this to work,there would have to be a large quantity of byoyomi time, and the bonus time should not be set too high. It should be set up so that both players know they will be stupid to attempt to finish the whole game in just main + bonus time. This way neither player will feel too disadvantaged when he ends up in byoyomi while his opponent still has some main + bonus time left. He will know that his opponent will almost certainly end up in byoyomi time also before the game is over.