Another variation of 'Tsuken-nobi joseki' dangers: this hamete is one of my all time favorites. I have used it many times with great success against some of my stronger Go students. I have enjoyed using this hamete against one of my sho dan and 4 dan students. I took a particular perverse delight in trouncing my 4 dan student\; but when we went over the game afterwards, I would quickly gloss over this hamete position by stressing another part of the board, hoping he would forget the hamete position.
Eventually he figured out how to respond correctly. Reluctantly I will show you it's secrets. White has just played a hamete at 'q17'. How would you respond?]
(
;
AddEmpty[pc][qf][pf][of][pg]
Comment[The following sequence illustrates how we arrived at the current position.]
;
White[qf]
;
Black[pf]
;
White[pg]
;
Black[of]
;
White[pc]
KO[]
)
(
;
Black[oc]
Comment[Black one at 'p17' and the following sequence end with White ten at
'q11', is the usual and worst sequence for Black.]
;
White[qc]
(
;
Black[qd]
;
White[ob]
;
Black[nc]
;
White[nb]
;
Black[mc]
;
White[og]
;
Black[ng]
;
White[pi]
Comment[After this exchange White has been fortunate to take both the corner
and side, leaving Black pinched between the two White groups with an over-concentrated group of stones. This position also leaves behind an interesting 'aji' point at 'p16', with plenty of mistakes for Black to make. :=)]
;
White[od]
Comment[The White move at 'p16' threatens a connection from the White corner
group to the side group.]
(
;
Black[nd]
Comment[If Black plays at 'o16', White will connect.]
;
White[rd]
Comment[After White at 's16', Black cannot stop White's connection. White has
now taken the corner and side, and Black has an over-concentrated position.]
)
(
;
Black[pe]
Comment[Black at 'q15' is also a very poor choice for Black.]
;
White[nf]
;
Black[ne]
;
White[rd]
Comment[Again, the White group connects on the bottom.]
)
(
;
Black[qe]
Comment[Black at 'r15' prevents the connection, but Black's shape will look
very silly, as shown in the next diagram.]
;
White[nf]
Comment[This is a humiliating shape for Black. ]
)
)
(
;
Black[qe]
Comment[Black at 'r15', instead of 'r16', is not much better.]
;
White[ob]
(
;
Black[nc]
;
White[nb]
;
Black[mc]
;
White[og]
;
Black[ng]
;
White[pi]
Comment[Black's position is still too over-concentrated.]
)
(
;
Black[nb]
Comment[Black at 'o18', instead of 'o17', will give Black to corner, but at a
price.]
;
White[qd]
;
Black[pe]
;
White[nc]
;
Black[od]
;
White[mb]
;
Black[pb]
;
White[na]
;
Black[qb]
Comment[After this exchange Black has taken the corner, but his stones are over-concentrated. The Black group's expansion is also limited by the two White groups. White should not be afraid of the weakness at 'r13', it's too small to consider.]
Letter[qg]
)
)
(
;
Black[ob]
Comment[Black at 'p18' makes life too simple for White.]
;
White[re]
Comment[White has cheated Black out of his corner.]
)
)
(
;
Black[qc]
Letter[jd]
Comment[Without a Black stone at the handicap point 'k16', Black one at 'r17'
is not a good move.]
;
White[oc]
;
Black[qe]
;
White[qb]
;
Black[rc]
;
White[lc]
Comment[Again, the Black stones are over-concentrated and limited in expansion
by the two White groups.]
;
AddEmpty[lc][qb][rc][qe][qc][oc]
AddBlack[jd]
Comment[With a Black stone at 'k16', Black can play the following sequence,
but this is only the second best for Black.]
;
Black[qc]
;
White[oc]
;
Black[qb]
Comment[In this case Black plays at 'r18, instead of 'r15'.]
;
White[qe]
;
Black[od]
;
White[nc]
;
Black[qd]
;
White[ld]
;
Black[pi]
Comment[As I said before, this exchange is better for Black, but only the
second best choice. ]
)
(
;
Black[qe]
Comment[Black one at 'r15' is the best play for Black, with or without the
side handicap stones.]
(
;
White[qc]
Comment[After the White two at 'r17' the next Black move is equally difficult
to find.]
;
Black[nc]
Comment[Black three at 'o17' is the second tesuji needed to thwart White's
plan.]
;
White[nb]
;
Black[mb]
(
;
White[ob]
;
Black[mc]
;
White[qg]
;
Black[rd]
;
White[rc]
;
Black[og]
Comment[After this exchange, Black has a strong outside influence, and White is
separated. ]
)
(
;
White[oc]
Comment[What happens if White plays at 'p17' instead of 'p18'?]
;
Black[ob]
;
White[nd]
;
Black[mc]
;
White[qg]
;
Black[rd]
;
White[od]
;
Black[og]
Comment[This exchange leaves White precariously posed.
Black has a better outside position, and the two White groups are eyeless and without any outside reliable influence.]
)
)
(
;
White[oc]
Comment[White two at 'p17' is not very good for White.]
;
Black[mc]
(
;
White[nd]
;
Black[md]
;
White[ne]
;
Black[lf]
;
White[mg]
;
Black[og]
Comment[After Black at 'p13', White must worry about his two weak stones on
the right and the weakness in his knight move; if these White stones are cut
of from the outside, they may die in the corner.]
Mark[pg][qf]
)
(
;
White[qg]
Comment[White at 'r13', instead of 'o16' is an overplay.]
;
Black[qc]
;
White[qb]
;
Black[rc]
Comment[This exchange leaves White in a very weak position.]
)
(
;
White[rc]
Comment[White at 's17' surrenders the outside to Black.]
;
Black[qg]
Comment[After this sequence, Black has a very good outside influence.]
