GoDave89: I agree with semelis. The argument that the large ko is for the whole corner seems weird, since the whole corner is lost anyway :D
caranthir: Is there not a ko? I see no way to win the corner outright if B3C3C2A4. See the position above (as an SGF, because at least for me, "link current position" just gives the initial position plus some move coordinates.) For now, I added that as an alternative course of action.
semelis: Would be interesting to see what happens if instead of capturing the cutting stone allowing the connection at 1st line the defender stubbornly cuts. Maybe a button to choose "optimal" vs "stubborn" resistance ?
caranthir: Most plausible scenario after the stubborn cut seems to be a large ko involving all of the corner. Modelling it would not apply so well in this kind of artificially isolated local setting. Anyway, in a game, if there are good threats, then the stubborn course of action could of course even be optimal.
Is there not a ko? I see no way to win the corner outright if B3 C3 C2 A4. See the position above (as an SGF, because at least for me, "link current position" just gives the initial position plus some move coordinates.) For now, I added that as an alternative course of action.