I ignored some invasion moves by Black. How should I have responded?

Hey, thanks so much for the detailed response! You gave me a lot of really good and helpful pointers. Hope you don't mind a few questions:



I'm not sure I understand. Do you mean I shouldn't try to contain Black unless I have stones in the center? I wanted a wall for influence and center territory.



Didn't I do this with move 74? How should I do this?



Yeah, it did. I had thought Black's play was a huge overplay and I could just surround it, since it didn't have much space to live. How do I tell whether I should go over or under Black?



At the time I thought that a 3-3 invasion would give Black strong outer walls and reduce my center territory. Isn't it bad to give Black those walls?



Good point. Where would you suggest? N15? L17?



I had thought it would be useful to have it in the center so that my groups could run to as well as to build a large moyo. Sort of like Shusaku's "ear reddening move" http://senseis.xmp.net/?EarReddeningMove

Why is that wrong?



Yeah, I see I pushed Black down and it cut off that chain. So are you saying I should never/rarely make a shoulder hit? Or just not when it can cause Black to cut off my group?



See, at that point it looks like Black doesn't have much room for an eye base. At what point do I say "Ok, Black clearly overplayed and can't make it live, so surround"?



Clearly my judgment is off here because it looked pretty dead to me. Where would I play 118 at to focus on killing it?



That's exactly how I felt! Actually that's how I feel in most of my games. So how do I work on properly shoring up the dam?



Does that mean I shouldn't do it? You're just talking about the first 70 moves or so, right?




This is all great advice. Can you elaborate further on the shape weaknesses I should have fixed up, and the "trick plays" by Black? They were clearly too tricky for me to notice.

Thanks again!

True, but if there are friendly stones on the other side of the board it's easier to make effective use of said influence. In the center territory occurs as a result of middle game fighting. I will link you a game where center influence was used well.

Playing No. 70 at J12 would've been better, at least to begin complicating things for Black.

K5 would allow you to make good use of the 3 White stones near the lower right corner.

A 3-3 invasion is good if the center is already crowded and the corner has enough space for a living group. A threat to link up with Q13 would make Black pay attention to an R17 invasion. 146 @ N17 is another good choice; you can threaten to run to your White group in the center.

I was thinking N15, since the L17 play would simply force Black to run out into the center and further endanger the P-meridian White group.

That move was No. 127, not No. 44. I would suggest - if you are up to the challenge - replaying Shusaku's 1846 game against Gennan Inseki 5 or 10 times. You will see that other stones were already in the vicinity, making move 127 all the more grimly effective

Shoulder hits are usually defensive, so it is better to use them for, let's say, defining territorial boundaries in the endgame or strengthening your own group in the middle game, albeit at the cost of strengthening your opponent's stones as well.

Just put pressure on Black to run out into the center, where it can be attacked and maybe even killed; enough White stones were available in the area. The attachment of Black 87 would be less effective with the move I advised.

In the second game, 118 would be at J10 to begin closing it off. If that Black group cannot be killed, at least it can be reduced. Black 119 would be at H14 as he will try to break out and eat a couple of adjacent White stones. White 120 blocks at H15. Black will go out at J15, but by now White's focus should be on connecting the H12 and H13 stones with J11 or H11.

Both your opponents seemed skilled at fighting, so you may want to do middle game tsumego to improve your reading in this area. As well, take your board & stones out and replay a professional game by, say, Takemiya Masaki, to see how a strong player deals with a fight. In the meantime, though, avoid fighting until you have sufficiently strong groups at different locations across the board.

In this game, White lets Black develop territory in exchange for center influence. Watch how White uses it.



Developmentally speaking, I'd say it's rather slow. It's better to have light formations all over the board. A big group covering 30% of the board can be a headache to manage later on in a game.

I did make mistakes playing as White in this 2-stone handi game on IGS. However, Black made several mistakes, including some very obvious ones.



Generally, I avoided fighting since this would favor Black in a handi game.

In the second game, No. 26 should have been played at P16 instead of Q16. The R16 stone can be abandoned; threaten to connect out R16 and Black plays at Q16. Then White plays at N15 to begin pressuring the N17 Black stone. From here a few things can happen. One is leading the P-meridian White group out into the center and, in the process, threatening to link up with the two Whites on the R-meridian. In fact, strengthen that group by leading it out into the center and threatening to link up with the White group at the top.

White 28 should be at P13. A play at O14 ony helps Black fix up his shape further. After 28, Black 29 at O14, White 30 @ O14. In the process you will threaten to link out the 2 White stones on line 14. If these are successfully linked out, you can begin attacking the 2 Black stones on line 12.

The "trick plays" by Black were actually tesuji. Doing plenty of tesuji problems will help you to apply them and recognize when they occur. To fix up the shape weaknesses, I'd replay professional game records to observe how good shape is formed. Doing life & death, tesuji, and vital point problems will help train your eye to read out possible scenarios and distinguish good shape from bad.