(;CA[UTF-8]ST[2]AP[GOWrite:3.0.10]GM[1]SZ[19]FF[4]TM[3600.0]PM[2]EV[6th European Pro Qualification]PB[Lukas Podpera]WR[7d]DT[2021-10-30]PW[Stanislaw Frejlak]BR[7d]KM[7.5]PC[Leksand, Sweden]RO[EPQ Final game 2]GN[EPQ (Stanislaw Frejlak W - Lukas Podpera B)]FG[771:]OT[3x30 byo-yomi]C[Commentary by Robert Jasiek starts at move 263]RE[W+0.5]US[Tony Claasen]SO[https\://www.eurogofed.org]RU[Chinese] ;B[qd];W[dp];B[pq];W[dd];B[nd];W[po];B[qo];W[qn];B[qp];W[pn];B[nq];W[pj];B[cq];W[cp];B[dq];W[ep];B[fr];W[cf];B[fc];W[lc];B[ic];W[pd];B[qc];W[pf];B[pc];W[ec];B[fd];W[me];B[dk];W[ho];B[gq];W[gp];B[ch];W[fb];B[gb];W[eb];B[eg];W[jd];B[jc];W[kd];B[he];W[op];B[oq];W[ne];B[rl];W[ql];B[qk];W[pk];B[qm];W[pl];B[rn];W[pm];B[rm];W[hq];B[hr];W[fq];B[gr];W[cm];B[cl];W[dm];B[fk];W[gj];B[bd];W[be];B[ji];W[gk];B[fj];W[gi];B[lj];W[jk];B[lh];W[fl];B[fh];W[jg];B[ll];W[km];B[lm];W[kn];B[ni];W[qe];B[od];W[pe];B[md];W[le];B[ph];W[oh];B[oi];W[pi];B[og];W[qh];B[nh];W[nb];B[ob];W[nc];B[oc];W[re];B[rd];W[sd];B[sc];W[se];B[rb];W[mg];B[rj];W[ri];B[kc];W[ld];B[lb];W[cj];B[bk];W[bj];B[bm];W[dj];B[ej];W[bh];B[bg];W[cg];B[bi];W[dh];B[ah];W[ci];B[dg];W[bh];B[de];W[cd];B[ch];W[eq];B[er];W[bh];B[ce];W[bf];B[ch];W[bq];B[aj];W[bh];B[bc];W[ag];B[cb];W[fi];B[br];W[ee];B[df];W[ed];B[ff];W[gc];B[gd];W[cc];B[db];W[bb];B[ab];W[ba];B[ca];W[ad];B[aa];W[bb];B[ba];W[hb];B[hc];W[ga];B[gc];W[ae];B[ac];W[da];B[fe];W[dc];B[ea];W[fa];B[ef];W[da];B[bp];W[bo];B[ea];W[ha];B[aq];W[ln];B[ih];W[ao];B[ib];W[da];B[co];W[cn];B[ea];W[mk];B[ia];W[kj];B[jf];W[ki];B[kh];W[li];B[mh];W[kg];B[jh];W[if];B[lg];W[kf];B[ig];W[je];B[oe];W[of];B[nf];W[mf];B[ng];W[ie];B[jj];W[kk];B[ij];W[pg];B[gh];W[ik];B[iq];W[mp];B[mj];W[lk];B[nk];W[nl];B[io];W[hp];B[ip];W[in];B[lq];W[kq];B[lp];W[kp];B[mo];W[lo];B[np];W[lr];B[mq];W[jr];B[ir];W[os];B[mr];W[ms];B[ns];W[nr];B[or];W[mc];B[ns];W[nn];B[jo];W[ko];B[ls];W[qj];B[rk];W[kr];B[mn];W[mm];B[no];W[oo];B[hf];W[ok];B[hi];W[nj];B[hk];W[eh];B[hj];W[hl];B[mi];W[sj];B[sk];W[si];B[jn];W[jm] ( ;C[move value 5/6 mistake]B[oj] ( ;W[ap];B[bq] ( ;W[is] ( ;B[hs] ( ;W[oa] ( ;B[pa] ( ;W[na] ( ;C[game losing move At this moment, the strategic consequences of area scoring are relevant. Instead of winning due to ordinary endgame value calculations, dame ko fights over delaying connection of the last ko become relevant. In such a ko, the area move value is 4/3. If dame do not provide compensation, either Black or White gets 2 points in the ko for a difference of 4 points in 3 local plays. For comparison, in an ordinary ko fight under area scoring, one excess dame provides a 2 points compensation because either Black or White gets 1 point on its intersection. The last ko and the excess dame share a locale. In an ordinary ko fight, the area move value is 2/3.]B[la] ;W[js] ;C[Type 10 remainder 0 (one ko open for Black minus one ko open for White) odd number 9 of dames (including teire) White to move no ko fight White will get the last dame.]LB[oh:A][nk:B]B[id]MA[kb][mb][ma][lf][jp][jq][ks][ms][pp] ;W[pp];B[jq];W[lf];B[jp];W[mb];B[kb];W[ma];B[ms] ;C[last dame]W[ks] ;C[filling the kos is equal options]B[oh] ;MA[hd]C[W last move B 1 point W+0,5]W[nk] ) ( ;PM[2]FG[771:] ;C[area move value 2/3 correct]B[oh] ;C[simplifying]W[ks] ;B[ms] ;C[simplifying]W[nk] ;B[js] ( ;C[move value 1/2]W[la] ;B[ka];W[ma] ;MA[jq][mb][pp][jp][lf][kb]C[move value 1/2 dame ko fight afterwards See my paper Ko and Dame Endgames under Area Scoring http\://home.snafu.de/jasiek/kodame.pdf Type 12 remainder 1 (one ko open) even number D = 6 of dames the slave (White, for whom the ko is closed) to move T > D/2 Difference T of ko threats = the initial numbers of the king's ko threats minus the slave's ko threats\; ko captures, plays on dames, or passes are not called ko threats. dame ko fight the king (Black, for whom the ko is open) wins the ko]B[id] ;C[ ]W[is];B[do];W[eo];B[js];W[qa];B[pb];W[is];B[hn];W[im];B[js];W[sb];B[sa];W[is];B[bn];W[dn];B[js];W[qb];B[rc];W[is];B[co];W[do];B[js];W[kb];B[jb];W[is];B[an];W[co];B[js];W[mb];B[kb];W[is];B[fp];W[fo];B[js] ;C[dame ko threat creates ordinary ko threats, which are included in the number T]W[pp] ;B[lf];W[is];B[go];W[gn];B[js];W[qq] ( ;B[rq];W[is];B[ei];W[gl];B[js];W[rp];B[ro];W[is];B[di];W[ek];B[js];W[rr];B[qr];W[is];B[ck];W[al];B[js];W[sq];B[qq];W[is];B[nm];W[om];B[js] ;C[dame ko threat]W[jq] ;B[jp];W[is];B[ml];W[nm];B[js] ;C[A is not a ko threat]LB[dr:A]W[tt] ;MA[la]C[B wins ko to compensate 1 point loss B+1,5]B[is] ) ( ;PM[2]FG[771:] ;C[mistake]B[is] ;W[rq] ;C[sample variations]B[rp] ;W[sp];B[ro];W[qr] ( ;B[so];W[sr];B[rs];W[sm] ) ( ;PM[2]FG[771:];B[sr];W[sq] ( ;B[so];W[sm] ) ( ;PM[2]FG[771:];B[pr];W[so];B[qs];W[rs];B[ps];W[sn];B[rr];W[ss] ) ( ;PM[2]FG[771:];B[qs];W[so];B[rr];W[rs];B[pr];W[ps] ( ;B[qs];W[ps] ) ( ;PM[2]FG[771:];B[sn];W[ss] ) ) ) ) ) ( ;PM[2]FG[771:];W[id];B[la] ;C[not showing the dame ko fight]W[pp] ;B[kb];W[mb];B[ma];W[lf];B[jq];W[jp] ;C[B last move after winning the ko fight B+1.5]B[hd] ) ) ( ;PM[2]FG[771:] ;C[unnecessarily complicated correct]B[id] ( ;C[mistake]W[la] ;B[ka];W[ma];B[oh] ;C[simplicity]W[ks] ;B[ms] ;MA[kb][mb][pp][jp][jq][lf]C[dame ko fight afterwards Type 14 remainder 1 (one ko open) even number D = 6 of dames (including teire) the slave (Black) to move T <= -D/2 dame ko fight the slave wins the ko]W[nk] ;B[js] ;C[dame ko fight unshown]W[mb] ;B[kb];C[ ]W[pp];B[jp];W[jq] ;MA[is][kb][js]C[B last dame B minus 1 point B gets extra ko B+1,5]B[lf] ) ( ;PM[2]FG[771:] ;C[mistake]W[js] ;C[correct]B[ma] ;W[mb];B[ka];W[nk] ;MA[ks][ms][jq][jp][pp][lf]C[dame ko fight afterwards Type 12 remainder 1 (one ko open) even number D = 6 of dames (including teire) the slave (White) to move T > D/2 dame ko fight the king wins the ko]B[oh] ;C[dame ko fight unshown]W[ks] ;B[ms];W[pp];B[jq];W[jp] ;MA[ma]C[B last dame B gets 1 extra intersection in ko B+1,5 final passes and ko connection unshown (also in some other variations)]B[lf] ) ( ;PM[2]FG[771:] ;C[correct]W[ma] ;B[la];W[js];B[oh];W[nk];B[ms];W[ks];B[kb];W[mb];B[pp];W[jq];B[jp] ;C[W last move W+0,5]W[lf] ) ) ) ( ;PM[2]FG[771:];W[ma] ) ) ( ;PM[2]FG[771:];B[ma];W[pa];B[na];W[mb] ) ) ( ;PM[2]FG[771:] ;C[TOSTUDY]W[ma] ) ) ( ;PM[2]FG[771:] ;C[TOSTUDY]B[ma] ) ) ( ;PM[2]FG[771:];C[better]W[ma] ) ) ( ;PM[2]FG[771:] ;C[TOSTUDY]W[ma] ) ) ( ;PM[2]FG[771:] ;C[move value 1 correct? At this moment, Black can win the game due to endgame move value calculations and a ko fight.]B[ap] ( ;C[larger than A]LB[oh:A]W[oj] ( ;C[equal options ABCD afterwards even number of dames ]LB[is:A][id:B][la:C][oa:D]B[oh] ( ;C[mistake]W[is] ( ;C[mistake]B[hs] ( ;C[mistake]W[js] ( ;C[mistake]B[oa] ( ;C[mistake]W[id] ( ;B[la] ;MA[jq][mb][pp][jp][lf][hd][ks][ms][ma][kb]C[even number of dames (incl. teires)]W[na] ;B[kb] ;MA[ma][mb][lf][pp][jp][jq][hd]C[Type 15 or 16 depending on whether the king has T > (D-1)/2 ko threats to win the dame ko fight. Otherwise, there would be no ko fight. Since the ko is larger than a basic endgame ko and affects internal tactics in Black's region, reading this ko fight is not straightforward. remainder 1 (one ko open) odd number D = 7 of dames the king (Black) to move ]W[ks] ( ;C[If B cannot win the dame ko fight...]B[ms] ;W[pp];B[hd];W[mb];B[ma];W[lf];B[jq] ;MA[bq][pa][nk]C[W last move B 1 point W+0,5]W[jp] ) ( ;PM[2]FG[771:] ;C[If Black can win the dame ko fight...]B[pp] ) ) ( ;PM[2]FG[771:];C[better]B[ma];W[na];B[ka];W[mb] ;C[see similar variation W does not have more ko threats around A. Also note that B has ko threats wound B.]LB[ar:A][qg:B]B[pp] ) ) ( ;PM[2]FG[771:] ;C[better, prevents Black from creating a ko there threatens A]LB[ka:A]W[ma] ;B[la];W[id] ) ) ( ;PM[2]FG[771:];C[better]B[ma];W[na];B[oa];W[mb];B[ka];W[id];B[pp] ) ) ( ;PM[2]FG[771:];C[better]W[ma] ) ) ( ;PM[2]FG[771:];C[better]B[ma] ) ) ( ;PM[2]FG[771:];C[better]W[ma] ) ) ( ;PM[2]FG[771:];B[oa] ( ;C[mistake]W[mb] ( ;C[mstake]B[la];W[is];B[hs];W[js] ;MA[jq][pp][lf][jp][na]C[odd number of gote dames 1 ko open for Black]B[id] ( ;C[suppose W does not fight ko]W[ma] ;B[kb];W[ks];B[ms];W[pp];B[na];W[lf];B[jp];W[jq] ;MA[bq][hd][nk][pa]C[B last move B 2 points B+1,5]B[oh] ) ( ;PM[2]FG[771:] ;C[suppose W fights ko]W[oh] ( ;C[suppose B loses ko]B[kb] ;MA[jq][pp][jp][lf][ma][na]C[even number of dames]W[ph] ;B[ms];W[pp];B[ks];W[jq];B[jp];W[lf];B[na] ;MA[bq][oh][ph][hd][nk][pa]C[W last move B 2 points W has ko W+0,5]W[ma] ) ( ;PM[2]FG[771:]C[ ] ;MA[jq][pp][lf][jp][na]C[B must fight ko odd number of gote dames]B[ph] ( ;C[dame ko threat due to the remainder 1 of remaining kos, the slave (White, for whom the ko is closed) to move, previously odd number of gote dames, the ko fight is ordinary, is not a dame ko fight, the ko move value is 2/3, the dame ko threat is futile]W[pp] ;C[B wins ko but W executes dame ko threat]B[oh] ;W[lf];B[kb];W[ma];B[ms];W[ks];B[na];W[jq] ;MA[bq][hd][nk][pa]C[B last move B 2 points B+0,5]B[jp] ) ( ;PM[2]FG[771:] ;C[W must play ordinary ko threats to possibly win the game]W[ks] ;B[ms];W[oh];B[hn];W[im];B[ph];W[kb];B[ka];W[oh];B[do];W[eo];B[ph];W[ma];B[jb];W[oh];B[bn];W[dn];B[ph];W[ar];B[as];W[oh];B[co];W[do];B[ph];W[bs];B[cs];W[oh];B[an];W[co];B[ph];W[ra];B[qa];W[oh];B[fp];W[fo];B[ph];W[sb];B[sa];W[oh];B[go];W[gn] ;C[B wins ordinary ko fight]B[ph] ;W[pp];B[oh];W[jq];B[jp];W[lf] ;MA[bq][hd][pa][nk]C[B last move B 2 points B+0,5]B[na] ) ) ) ) ( ;PM[2]FG[771:] ;C[Better?]B[ma] ;W[na];B[ka] ( ;W[is];B[hs];W[js] ( ;B[id] ) ( ;PM[2]FG[771:];B[la] ) ) ( ;PM[2]FG[771:];W[id];B[is] ) ( ;PM[2]FG[771:];W[la] ) ) ) ( ;PM[2]FG[771:];C[better]W[ma] ) ) ( ;PM[2]FG[771:];B[ma];W[na];B[oa];W[mb];B[ka] ) ) ( ;PM[2]FG[771:] ;C[threatens A prevents possible ko at B but enables ko at C]LB[ka:A][la:B][oa:C]W[ma] ) ) ( ;PM[2]FG[771:] ;C[TOSTUDY]B[ma] ) )