I don't know is Dan is still around but back in the days of the old GD board, I remember him being a big proponent of not using shoulder hits. Why is that? For those that don't know, this is a shoulder hit.

Click Here To Show Diagram Code

[go]$$Bm1 Corner
$$ ------------------
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . , . . . . .
$$ | . . . . . . . . .
$$ | . . . 1 . . . . .
$$ | . . . . 2 . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

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From what I recall, a shoulder hit on the 4th line as in your diagram, offers your opponent an opportunity to secure 4th line territory. Played against a 3rd line stone however seems pretty common. What I remember as being called bad was playing a shoulder hit under a 4th line stone.

Click Here To Show Diagram Code

[go]$$Bm1 Armpit
$$ ------------------
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . , . . . . .
$$ | . . . . . . . . .
$$ | . . . 1 . . . . .
$$ | . . 2 . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

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Patience, grasshopper.

I don't remember this person or their shoulder hit views, but it's easy to 'prove' them wrong by constructing a position where a shoulder hit is a good move.

I assume what they meant is that it is also easy, perhaps much easier, to construct a position where the shoulder hit is a bad move. Amateurs are quite good at this exercise, but they often forget not to include the shoulder hit.

In your example, the shoulder hit refutation (disregarding ladders/some massive moyo etc.) is to just push along the fourth line then jump, taking territory and leaving white's group fairly light but without territory.

Shoulder hits are much more common against third line stones, in which case white is usually either:
a) Invadinga moyo, and planning to use the aggressive nature of the shoulder hit to get forcing moves if the opponent tries to attack strongly.
b) Creating a moyo, and therefore willing to solidify the opponents position and take territory in return for the influence given by the light shoulder hit stone.

Both of these highlight the nature of the shoulder hit as allowing the opponent to take easy territory; the opponent's stone is not threatened, but both situations are such that giving the opponent easy territory is not a problem. Amateurs quite often play the shoulder hit when this is not justified, leading to problems.

An example of b:

Click Here To Show Diagram Code

[go]$$Bm1 Corner
$$ ------------------
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . X . . X . . .
$$ | . O . X . . . . .
$$ | . . . . . . . . .
$$ | . . O 3 . . . . .
$$ | . . 6 4 5 . . . .
$$ | . . 2 1 . . . . .
$$ | . . O . . . . . .
$$ | . . . , . . . . .[/go]

This common sequence trades a solidification of white's position for a few stones on the outside. Black can now tenuki, usually, but white's ability to jump around has already been compromised. If black has no supporting stones, white thinks he has the better deal as black has given him territory for nothing solid.

This is the worst way you can look at any sort of go problem. What is the context of the shoulder hit? Are you trying to flatten down your opponent's moyo, or are you trying to make it so you lean on the enemy stone to get strength for life? Or are you just playing the move because you can? There's more to the move than just it's name. The description doesn't tell you at all what the game itself is like. I'm sure there was more to the person's argument than just "the shoulder hit is bad".

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I know nothing.

When I think of shoulder hits, I always remember this game:


Where 33 is an illustration of amnal's 'a' and 46, 'b'. I try to capture the feeling of these moves with my own shoulder hits.

Though, it's important to remember there are other shoulder hit joseki too.

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Hence why I'm asking. All I remember was him saying that they were bad. I don't remember the circumstances of that.
Is Dan still around? I haven't been here much myself, since my comp got f'd.

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Fried? A fitting end for a chef's computer.

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Patience, grasshopper.

Without claiming any authority, my advice about this would be: don't try that at home! These shoulder hits, and particularly the first one, look like high-level moves to me, even though they might be basic middle-game joseki moves. The top right is still unsettled, there is a danger of ending up with two weak groups, and it is hard to say what happens with the moyo on the bottom side. If it were my game, I would never have dared to play either of those shoulder hits, because they feel like overplays to me.

Of course, the fact that these players did, in fact, play those moves nicely illustrates the crudeness of my intuition...

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When in doubt, play the most aggressive move

Asking what's wrong with shoulder hits is like asking what's good about a hane.

Clearly you should never play shoulder hits, never make bad shape, always play the vital point, extend when attached to, extend when crosscut, hane at the head of two stones, hane at the head of three stones, connect when peeped, play away from thickness, play it if it is big, urgent points before big points, don't get sealed in, use walls to attack, use handicap stones to attack, don't attach to weak stones when you are strong, the second line is the line of defeat, don't push from behind, kill your opponent with death in the hane, jump three stones from a two stone wall, capture cutting stones, never make empty triangles, the one space jump is never bad, strike at the waist of the knight's move, approach from the wider side, block from the wider side, play at the center of three stones, attack while taking profit, and capture with a net instead of a ladder.

Isn't Go so easy?

My best attempt to answer the question, as phrased, is the following.

The shoulder hit invariably leads to an inferior result, locally. You cede territory, and often make a stone that is not that strong, stronger.

Essentially, the shoulder hit is always bad, and should never be played except those situations when it should.

Those situations are when the local loss results in an overconcentration and/or reduction of a strong position, a position difficult to attack anyway, and leaves you with a stone or stones that is/are useful.

I don't think it's really a shoulder hit if it's on the fourth line like that...

Are you sure he wasn't talking about the armpit hit? That really usually is bad...

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I don't know. It was you that told me. I'm guessing that I didn't interpret that properly. I remember it was about a year ago. I posted a game and you said to not do shoulder hits. You were quite specific about that.

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Lol, me??

Either I mistyped or you are misremembering.

I strongly suspect I was talking about "armpit" hits (below). Usually this is only ok when 2 is making emergency life for a group. 8k-20k players really seem to like this move for some reason.

Click Here To Show Diagram Code

[go]$$Bm1 Armpit hit
$$ ------------------
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . . . , . . . . .
$$ | . . . . . . . . .
$$ | . . . 1 . . . . .
$$ | . . 2 . . . . . .
$$ | . . . . . . . . .
$$ | . . . . . . . . .[/go]

_________________
That which can be destroyed by the truth should be.
--
My (sadly neglected, but not forgotten) project: http://dailyjoseki.com