First is

. It seems a quite normal choice. At the same time we should realize that White is playing Black's game here. White basically agrees that the right side is the most urgent part of the board. However, the first four moves of this game have been played often by the pros. By a very wide margin

tends to be an approach in the upper left, the area of asymmetry on the board. In this game, and in a minority of pro games, Black plays first against the upper right. After

where should White play? One alternative choice would be to simply finish the top left with one of the "a" points below. Another would be to approach the lower left at

with the intention of setting up a Kobayashi style formation with

or "b". This says that White believes that he can compete in a moyo building contest and that the upper left will be more advantageous for White than the lower right will be for Black. I am not saying what is best but they are different ways of seeing the position.
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- Click Here To Show Diagram Code
[go]$$Wc
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Second is

. I am with Bill in not liking the slide. It just gives up the invasion at R3 for little benefit to White. I think Bill's 2-space extension is interesting. If Black responds the the kick at

below, White plays the continuation with

and

. Suddenly Black is staking the whole game on the lower right territory. If Black plays on the left instead, then the Black right side has weak points at all the points marked "a" and almost none can be considered secure territory. I think the addition of the R3 stone by Black in the game was a big help to the right side.
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- Click Here To Show Diagram Code
[go]$$Wc
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Third is

. Interestingly GoGoD has nearly 21,000 examples of a 4-4 stone and a 3-4 stone in this configuration on an otherwise empty half board. There are 9,300 cases of Black playing "a" next and 6,000 cases of playing "b" next. There are also (count them!) 39 cases of Black playing at

. The most frequent choice for a reply is actually not in the upper left at all, it is

. Looking at the games, this is most often played from a White position in the lower right. If we think about it, White

prevents Black from playing J3 next, which would both attack White and make a double-wing formation. In the upper left, White can think of "d" and "b" as miai. BTW, in the cases where White does not approach the bottom left with

, he almost always just makes a shimari in the upper left.
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- Click Here To Show Diagram Code
[go]$$Bc
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