Life In 19x19

18(S)-19

I knew there was something fishy about this ko! Black could back out now and connect at 16-18 or else then I count at least a 2 step ko to avoid quite a bit of damage. If black pursues this line then I'm confident black still has lots of threats but I should be able to get some good compensation with three moves elsewhere.

I don't think I'm particularly doing this Malkovich thing very well. I keep cutting my comments a bit short in favour of getting my move played sooner.
What I meant about black resisting instead of backing off at 16-18 was the following read:
B17-19, w16-18, b19-19, w15-18, b14-17, w14-18, b13-17, w13-18, b12-18, w16-19, b15-17, w18-18, b18-19, w19-15.
However I'm not sure I can't cut through and do better.

If black does back off then I have to work out if this corner is large enough for me to capture the ko. There are ways to work out a ballpark value of a move in a step ko situation like this but I'm quite sceptical of these methods and I think they break down a little bit when the balance of threats is uneven like this. Moves around the centre left are not small

16-8
Q8

I can't tell if this was a good or bad ko threat for him. Oh well. I'm just playing relatively normal and biding my time. I doubt there's any way I would use a different exchange for this weakness, so it's a fine ko threat.

I'm moving back into college for the second semester - might be a little slow to move for a bit.

Black's play suggests that he would play a ko threat and then recapture the ko if I played the trigger move, but I'm a firm believer in playing the board and assuming the strongest move for your opponent. I think blacks strongest move would be to back of and fix rather than play ko so in order to avoid that I should not exchange the ko capture (This is an interesting discussion point actually, I'm sure some people would argue that I should factor in the way black has played.)
I'm of course hoping that black isn't playing this way because he has outread me or because he can see a stone I can't!
I haven't offered a trigger here because I'm not 100% sure if I can do better than I thought and black will back out with 15-18 now.

14-17, O17.

I kinda skipped reading of this variation when I played my last move, assuming my 5th line stone was strength and not weakness, which was definitely hasty. Now I know that his move is genuinely dangerous in this joseki! I wrote up my findings concurrently while I was reading this move out but lost it all and don't feel like writing it all up again.

I'll just say that I think the best result I can force is 2step-ko for him, but where he has 7 local ko threats. I definitely should have just tenuki'd the last move, I'm now down in total by like 20 points again

At least it's a complicated game. This is why you always read out the violent response!

13(N)-18

Great (I hope!) progress as planned. Black could hane next and allow me to capture one stone above and get into the territory from the centre I think. That may be the best choice.

The variation he offered in his trigger is a little worse for me than this one. I wonder if he'll accidentally use some extra locals due to misreading here? I realized last night that when he denied my trigger he basically allowed me to skip playing a ko threat, which was definitely wrong.

I believe the correct sequence should be to play w 18-18, b 18-19, w 19-15, b 14-19, and w 19-17 starts a two-step ko where white uses 7 local ko threats associated with the cut at 13-17.

12(M)-17

He did waste the ko threats, like I thought! Also, he disabled himself from going into the other variations, but they were probably worse for white. Only 5 extra locals for him now!

12(M)-16

Then if b 12-15 or 10-18 or 11-19 then open next hidden text..

Then I play 19(T)-15

Arg! Big missread during this whole cut-at-16-18 sequence. I didn't realise that black could hane at 13-18! Somehow I only read that if I cut black would have to extend from the second line stone to protect it - I overlooked that he could atari first. Initially I was really frustrated at myself as this is so much worse than the situation I thought I had. My internal win rate (both software and hardware are questionable) dropped from something pretty good to maybe 5%. However I have become slightly more balanced. Compared to the ko I was previously fighting they are both (I think?) direct kos, this one has doesn't stand to ruin the top side as much as I did previously so there is a direct loss however black could afford to play such a risky ko because he has such a good balance of threats. By playing out this sequence that doesn't quite work I have gained a couple more local threats. It's tough to say, but this might be enough to get me better compensation when I loose the ko? I've only just realised while typing that I think I could have still succeed in creating a step ko depending on how black chooses to fight it, which might be enough to make it worth it. My internal win rate is bubbling back up again slightly. The reason I'm playing this sequence of moves that look like local threats is that black can stop them working as threats when I start the ko (w 19-15,b15-17, w19-17, b18-17, w16-19..) after this sequence I have only 2 liberties so these moves I just played wouldn't be good threats

18-18
S18

Well, now he's going into a simple direct ko where I'm making the first global threat. I definitely think this is not as good for him as the two-step variation where he gets 7 local threats - it's not like making ko threats is free for me, even if I do have a lot of decent ones.
In fact, I think he would have been better served by the clamp at 12-18 after I atari at 13-16. I anticipated black takes, white atari under, and black throws in at 14-19 to be best there, which makes a direct ko that's a lot better for white.

Anyway, my first ko threat of choice has changed from the one I was going to play earlier. I'm going to make my first ko threat the atari at 5-14. That ko threat confuses the game more for him, I think. Actually, I have a very hard time figuring out the best response myself. You'd normally like to extend with white at 6-15, but it would give me more ko threats to do so.

I'm definitely feeling a lot better about this ko shenanigans than I was feeling before.

13(N)-19

Since I last played it 1917 has received 10 Oscar nominations so it must be good. Very happy with this development - more comment to follow

Disappointed in my reading again. I mentioned earlier a couple of local threats. One of these threats was 13-15 which doesn't work because black can just take a liberty away. I got one local threat at the top but I should have got two. If I had exchanged w 11-19, b 10-19 then I would be able to play 14-19 and then 11-18 as local threats instead of just 13-19 :/
Still, I really thought black should have played a ko threat instead of 18-18. Now I have my step ko for black. I will get three moves elsewhere which should compensate me for this corner well enough. I think I ought to properly count threats to determine if I will get something like the top left situation out of the bargain or not.

He triggered on me playing on top of one of my stones? I'm pretty sure I'm visualizing properly.

We're still wading through towards the ko. I'm thinking the most likely result is that I capture the top and he captures my bottom left 4 stones. Since I'd come out with sente there, it seems playable for me, though still I'd be a little worse.

I could have played 14-19 instead of 18-18 last move, and then it would have gone b 14-19, w 18-18, b 15-19, w 18-19, b 16-19. I would have captured the trouble stones in gote. The thing is, that's still a big loss, and I should be winning this ko anyway, so I'm evaluating it as slightly more black's equity than white's.