Well, my idea was to make the button neither a pass nor a play. Anyway, do you have an example of such a pass fight?

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Sum ergo non ero.

How so? What difference would that make? How would it work?

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The Adkins Principle:

At some point, doesn't thinking have to go on?

— Winona Adkins

The idea is to consider Button Go a way to fine-tune komi under area scoring rather than a compromise between area and territory scoring. This seems especially relevant now that AlphaGo says that the best komi value under area scoring (7.5) gives Black a sizeable advantage (55% win rate).

Because of this, komi 7 with button seems the best alternative, but ideally the adoption of this solution should be made in a way that optimal on-board scores (prior to adding komi and button) don't change. If the button lifts ko and superko bans, some positions yield a different on-board score than regular area scoring, so I'm arguing that maybe it shouldn't have that ability in order for the game to remain one and the same at its core, and in order for "komi 7 plus button" to be considered a legitimate komi for area scoring rather than a Go variant.

That's what I mean by the button not being a play: it's not taken into account by positional superko, whose concern is the board position, i.e. plays. But, of course, it's still not a pass: passing after the opponent takes the button doesn't end the game.

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Sum ergo non ero.

Perhaps one way of implementing that as a variant of AGA rules without a physical button is this way:

1) use territory counting;
2) play stops after two consecutive passes after the first pass;
3) the player making the first pass does not hand over a pass stone;
4) if the opponent of the player who made the first pass makes the last pass, she does not hand over a pass stone for that pass, either;
5) use 6.5 komi (presently).

With no physical button, just treat the first pass as the button.

_________________
The Adkins Principle:

At some point, doesn't thinking have to go on?

— Winona Adkins

Can anyone point me to an example of this? I thought I had understood it, but it was a delusion.

(This and the issue of one-sided dame, discussed before, seem strong arguments against implementing the button as the first pass and allowing two consecutive passes to end play.)

_________________
Sum ergo non ero.

@luigi
Maybe this is such a position:
http://www.dgob.de/yabbse/index.php?top ... #msg134089
I am not sure, if it matches exactly your question. But even if it does not, it is a very interesting position, so I post it without checking it. Everyone who is interested in go rules will like the position anyway.

It is about the difference between Ikeda T1 und Ikeda A3 rules.
(BTW to make these rules equivalent you have to change the Ikeda T1 rules, so that the player that passed second and finishes the 'normal' game plays the first move in the encore.)