Life In 19x19

So, I took another break from go recently and now returned, I am still trying to break through to SDK and beyond. I seem stuck, for the moment, at KGS 10 kyu. Here is a recent game I lost by about 20 points.



Anyway, here are things I think I did incorrectly/inefficiently in the attached game, where I play black:

15: perhaps should have finished up in lower right, playing trumpet connection?

21: I think closing corner is bigger than saving 2 stones in bottom right. I think this is the biggest move on the board, is it?

29: I sacrificed two stones and now wanted to defend my group. Did I play too far away? Or is my group OK and this is inefficient? (Should I play K17 or C6 or something?) I think this is a good move, but maybe too far away from Q5.

31-35: I pincer to extend from left enclosure. I do not know how to do pincer josekis very well, so I am sort of guessing about follow up. At 33, I play this because I do not want white to trap me in corner, but maybe this is not best?

37: I think this is a real mistake. I should have played N16 or something to destroy the lone white stone at N17.

43: I am worried about inside group. I do not think white's follow up at M17 is best. I think he should play at L14 or something to really split me and attack upper group; my mistake is not punished. Same for 47/48.

69: wasted move, or at least, accomplishes nothing.

73: Now I want to push/attack bottom left 2 stones. But I did not fix weaknesses in right-side black group which is weakened due to being sandwiched between strong right groups and having many cutting points. Should I have played K6, L7, K7, L6 or some move like that before playing F7? If not - is there a better attack than F7?

77: Maybe I worry too much about this group, and K7 would have been better.

137: D18 instead of hane at C18. Hane lets ko begin which obliterates P16 stones. If I play D18, white does not have enough room to live.

157: obvious big mistake, I do not even see that my stones will be in atari still. My apologies.

I appreciate all comments and wisdom from anyone of any strength and I hope I can sweep out the mistakes that are still holding me back.

Thank you!

Signifier wrote: .....
15: perhaps should have finished up in lower right, playing trumpet connection?
.............

is not in my joseki dictionary so I wonder how the experts would answer it. I like your taking the outside.
I don't know what a trumpet connection is, but I would play N15 for .
If w tenukis next N17 will be sente as it aims at Q2.

I made my comments before looking at yours. You recognized a lot of questionable moves.

I like to finish my comments first. Then I'll read Bill's, these will be far too excellent, I fear
is the ideal opportunity for the bamboo joint. ( No better joint than a bamboo joint )
first force ( at Q14, then defend )
After would you like to remove both and ? If yes how could you have accomplished that?

Bill already gave an excellent review, but to reiterate what I consider the few most important points:

absolutely cannot tenuki. You have invested a lot of stones to surround the W corner, but your outside position still has multiple cutting points and does not yet qualify as thickness. Spending one more move to ensure that six previous moves achieve their full potential is much more important than playing a single stone in a new area of the board.

is the right direction -- an extension from this wall takes precedence over almost any other move. (Bill's suggestion to make the wall even stronger might be equally good, but then W gets to play Q11 with room for a two-space extension on either side, so I am not convinced.) You worry that the game move might be too far from your wall, but actually it is too close. Your goal should not be to play so close that an invasion is impossible, but rather to play so far that you will make game-winning territory if W fails to invade, yet have a profitable attack if W does invade. After the game move, if W played safe outside reducing moves like L6 (immediately) and T6 (much later in yose), the B territory would become over-concentrated, and you would wish your extension was farther away.

absolutely cannot tenuki. You must take advantage of your superior position in the upper right to attack or make territory, otherwise all that great thickness could be wasted. You can stake out a larger territory in the upper right than your opponent can in the lower left, so there is no need to start reducing his territory now. N16 is a good idea, but much too modest -- W will just give up one stone on a very small scale. At the very least, play L15 or K15 and dare W to try something here. Bill's suggestion to press at Q13 is a middle-game joseki and would be very good in this position. After this move, if W tries to run with the O17 stone, B will easily make territory on the top side while attacking.