(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[6.50]
GN[2015 US Open Game 5]PW[Frederick King]PB[Brady]WR[3d]DT[2015-08-07]RE[B+0.50]
;B[pd]
;W[dd]
;B[qp]
;W[dp]
;B[fq]
;W[op]
;B[mq]
;W[qq]
;B[qm]
;W[pp]
;B[rp]
;W[or]
;B[jp]
(;W[cn]
;B[rq]LB[qj:A]C[Really big. Hurts white's base, and makes black A less mandatory]
;W[qr]
;B[fc]
;W[cf]
;B[jd]
;W[qf]
;B[qh]
;W[qc]
;B[pc]
;W[qd]
;B[pe]
;W[rf]
;B[pf]
;W[kd]
;B[ke]
;W[jc]
;B[kc]
;W[id]
;B[ld]
;W[je]
(;B[jf]
;W[ie]
(;B[fe]
(;W[if]
;B[jg]C[black is very happy to get this ]
;W[fg]
(;B[dc]
;W[cc]
;B[cb]
(;W[cd]
;B[eb]
;W[ed]
;B[gb]C[good result for black]
;W[hp]
;B[hq]
;W[iq]
;B[ip]
;W[gq]
;B[hr]
;W[gp]
;B[gr]
;W[fp]
;B[ig]
;W[gf]
;B[hg]
;W[ge]
(;B[nn]C[looks huge, but not the right direction]
(;W[mp]
;B[lp]
;W[mo]
;B[nq]
;W[on]
;B[om]
;W[pn]
;B[pm]
;W[lo]
;B[kp]
;W[mm]
(;B[ml]LB[qg:B][qh:C][ps:A]SQ[lg][mg][ng][og]C[Wrong direction for several reasons. 

I thought I was attacking white, but I'm not. White an always just live with A.

Plus, the weakness at B, means black can't expect much on the right side.

Finally, black's thicness that everything above  the marked area is already territory, not need to continue. Black also points in the lower right,whether he continues or not.

So this move is, at best, going to gain a few points in the center.

There are bigger moves.]
(;W[ll]
;B[no]
;W[np]
;B[nm]
;W[lm]LB[ll:D][ml:B][lm:C][no:A][ps:E]
;B[lk]
;W[kk]
;B[lj]
;W[kj]
;B[li]LB[nj:A]
(;W[qg]C[very big, but not the biggest right now]
;B[jl]
;W[kl]
;B[pg]
;W[rh]C[and the right side is damaged.]
(;B[fd]LB[if:A]
(;W[fi]C[A little passive]
;B[cm]C[a good start]
;W[dn]
;B[eh]
;W[fh]
;B[ff]
;W[gg]
;B[eg]
;W[dg]
;B[df]
;W[ci]
;B[ei]
;W[ki]
;B[lh]
;W[qi]
;B[ij]
;W[jm]
;B[fj]
;W[gj]
;B[gk]
;W[fk]
;B[ej]
;W[kd]
;B[lc]
;W[kf]
;B[le]
;W[hi]
(;B[ii]C[Not the best]
;W[hk]
;B[gl]
;W[hj]
;B[ch]
;W[bh]
(;B[dh]C[bah, missed tesuji]
;W[bg]
(;B[cq]
;W[fr]
;B[ir]
(;W[bp]
;B[eq]C[b gets lucky]
;W[dq]
;B[er]
;W[ph]LB[lk:A]C[big, and proof that plays around A weren't nearly as big as we both thought.

end of review]
;B[hl]
;W[ik]
;B[dr]LB[cp:C][ep:B][dr:A]
;W[fn]
;B[el]
;W[dk]
;B[ek]
;W[cl]
;B[cj]
;W[bj]
;B[di]
;W[bi]
;B[dm]
;W[bm]
;B[rk]
;W[qn]
;B[rn]
;W[qk]
;B[rj]
;W[qj]
;B[rr]
;W[hh]
;B[bc]
;W[bd]
;B[qs]
;W[oq]
;B[oh]
;W[oi]
;B[ni]
;W[pb]
;B[ob]
;W[qb]
;B[cp]
;W[bq]
;B[ep]
;W[do]
;B[br])
(;W[er]C[b gets nothing])
(;W[dr]C[or this]))
(;B[eq]C[honte]))
(;B[bg]C[attach - hane is the standard tesuji sequence]
(;W[dh]
;B[cg]
;W[di]
;B[bf]
;W[ce]
;B[bi]C[white is crushed])
(;W[cg]
;B[dh]
(;W[bi]
;B[ce]C[horrible for white])
(;W[bf]
;B[bi]
;W[ag]
;B[cj]C[white needs to submit, and black crushes the bottom]))))
(;B[hj]C[atari first?]
(;W[gi]
;B[ii]
;W[hh]LB[hk:A]
;B[ih]C[Not easy for white])
(;W[ii]C[white can connect, but it's annoying]
;B[gi]
;W[hh]
(;B[ji]C[black can't split]
;W[jh]
;B[jj]
;W[kg]C[b dies]
;B[kh]
;W[hf])
(;B[eq]C[just play a huge move, black is happy]))))
(;W[qi]LB[kj:A]C[If white gets this, black's moves in the area gained nothing.

Whites moves around A help the left side.]))
(;B[qi]))
(;W[dk]C[If white plays here, the whole left side might be his.])
(;W[fr]C[30 points]
;B[ir]
;W[dk]LB[lk:B][ml:A][ao:F][bo:E][eq:D][fr:C]C[A and B are worth far less than C and D.]))
(;W[fr]
(;B[ir]
;W[eq]TR[ao][bo][ap][bp][cp][aq][bq][cq][dq][fq][ar][br][cr][dr][er][as][bs][cs][ds][es]C[White's corner is worth at least twenty, and black's lower side is around seven points smaller this way.])
(;B[sa]
;W[ir])))
(;B[eq]C[Almost surely sente.]
;W[ep]
(;B[cj]LB[nd:A][rk:B][ml:C]C[white has more potential on the left side than black does on the right.])
(;B[cr]CR[fr][ir][es][fs][gs][hs][is]LB[cl:A]C[This is worth 30'ish.

White gets nothing in the corner, black has gained at least seven.

If white played first here, the corner would be worth at least 20 points, and probably quite a bit more.]))
(;B[cj]C[White's left side has more potential than black's right, so jumping in here is bigger.]))
(;W[fr]C[Black must answer.]
;B[ir]
;W[eq]CR[ao][bo][ap][bp][cp][aq][bq][cq][fq][ar][br][cr][dr][er][as][bs][cs][ds][es]SQ[iq][jq][jr][is][js]C[White has at least 20 points in the corner this way. Black has 5 on the side.]))
(;B[eq]C[This sequence is worth 30'ish points.

This move is almost certainly sente.]
;W[ep]
;B[cr]CR[iq][jq][er][fr][ir][jr][es][fs][gs][hs][is][js]LB[cl:A]C[White has lost all the points in the corner. If he takes gote here, he can gain maybe four? So assume white takes sente somewhere else.

Then compared to the variation, white lost 20 points, and black gained at least seven.

Plus if black get to continue at A, white's former thickness may become  a target.

If white defends against A, then black gets these huge moves in sente, so double the value.

So by my math, it is worth a minimum of 27, but black has follow-ups.

Jennie Shen says it's probably worth thirty.]))
(;W[ec]C[white can make things difficult for black]
;B[db]
;W[ed]
;B[eb]
;W[bc]
;B[fd]
;W[kd]
;B[lc]
;W[gb]
;B[fb]
;W[ig]C[not bad for white.]))
(;B[jb]C[now this sequence works for black]
;W[kd]
;B[ic]
;W[jd]
;B[lb]LB[if:A][kf:C][jg:B]C[there is no longer a ladder for whtie starting at C after the A-B exchange.]
;W[hc]
;B[ib]
(;W[hb]C[Whtie is too thin]
;B[hd]C[black can cut right away])
(;W[gd]
(;B[dc]C[black should play something greedy like this, rather than just connecting.]
(;W[cc]
;B[ed]LB[cb:B][hb:A][de:C][eg:D]C[Black has too many options. A-D are good])
(;W[fd]
;B[ed]
;W[ee]
;B[ec]C[black is happy to get the money this way too]))
(;B[fd]
;W[hb]
;B[gf]
;W[ig]
;B[gg]C[This way it's a fight]))))
(;W[kd]C[now the ko is good for white.]
;B[qe]
;W[re]
;B[jd]
;W[kb]C[annoying for black, white is making shape too easily]))
(;B[jb]
;W[kd]
(;B[ic]C[black wants this to connect and leave white with a floating group, but it doesn't quite work]
;W[jd]
;B[lb]
;W[kf]
;B[le]
;W[jg]C[playable for white due to the ladder])
(;B[qe]C[big ko threat]
;W[re]
;B[jd]
;W[ic]C[white has no threat]
;B[ib]C[good for black])))
(;B[jb]C[playing underneath might be easier]))
(;W[rq]C[This is probably sente]
;B[qj]C[fine for white.]))