For a ko, a player can virtual-force something if he can force the something while exceptionally he may always make a ko-capture on this ko immediately after the opponent's ko-capture on this ko unless that ko-capture was preceded by the player's ko-capture on a different ko.

Hi Robert, in the definition you gave above, there is a 43-word segment that has no comma whatsoever, making it very difficult to parse. May I suggest that you break this definition into two sentences or more?

I have yet to read your explanation but I shall attempt to do so later. But probably with a sentence structure that is easier on the readers, you might actually need less explanation.

Cheers!