posetcay: I get that this tsumego wants the player to show the double-ko sequence, but taking the stone at E17 first should be as good if not better even if there is a double-ko sequence. I couldn't find a good way to fix this issue without completely skipping the double-ko solution. Can anyone think of a clever fix?
caranthir: At least I don't have anything clever in mind. There have been annoyingly many problems which demand a double ko setup being presented, while just taking a ko first is usually simply the better move. In other problems I have modified I have simply accepted the ko-taking. I suggest that we do the same here and maybe add a comment shown to the player so that they are at least aware of the double ko, even if they only accidentally stumbled on the right answer.
1001kyu: After exchanging F4F3, playing F5 can be delayed by one move. I think this happens in both variations
caranthir: Isn't it suboptimal though. Next, opponent should capture at F15 and now we didn't get any ko chances to capture stuff but just the small connection.
Immanuel N: The case of double atari (P3) should be included as a correct solution too.
The order I did with white stones is: P1 (white), Q1 (black), Q2 (white), O2 (black), O4 (white), O3 (black), O5 (white), P5 (black), and then P3 (white) to make the double atari.
Ivan Detkov: This is just a ko. The correct solution is superior.
At least I don't have anything clever in mind. There have been annoyingly many problems which demand a double ko setup being presented, while just taking a ko first is usually simply the better move. In other problems I have modified I have simply accepted the ko-taking. I suggest that we do the same here and maybe add a comment shown to the player so that they are at least aware of the double ko, even if they only accidentally stumbled on the right answer.