FWIW, there is an argument for taking the diagonally opposite corner. By doing so White can force a parallel fuseki if each side takes a corner. If White takes an adjacent corner, Black can also force a parallel fuseki (again, assuming that each side takes a corner). Given that assumption, a parallel fuseki is equitable. If White plays in an adjacent corner instead, Black can make a diagonal fuseki, which may be favorable for Black.

One little revelation that recently made me change my thinking about the opening slightly was that komi gives white more advantage in a game of small territories. If you add to that the commonsense sentiment that a diagonal opening is less amenable to framework-based play, does it not immediately follow that a parallel opening favors black?

My view is that I do not know of any objective argument pro or con.

On the other hand, were Black to respond to White's initial approach move simply at 'a', it would be a better direction for his stones since then White would not have such an easy time of it on the right side; any waruichi (wedge) would be attacked. On the other hand, after Black's extension at 'a' and White's settling at or around 'b', Black will still be left with a good approach move at 'c'.

Therefore we might even question Black's pincer response as a poor direction of play. And in that light, certainly, also the diagonal fuseki.

Usagi, there are too many examples of pro games with diagonal fusekis for me to believe that anything of what you say on cross fusekis is true.

I saw an opening once that proceeded like this. Probably black was just a naive, yet rude beginner with no feeling for direction of play:

Click Here To Show Diagram Code

[go]$$c Black playing like a noob, probably around KGS 28k
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . 2 , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . 5 . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 3 . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . 4 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

One, in books, the diagrams are always presented from Black's view, as a courtesy to the person studying the game (who is assumed to be taking the black stones). There are a few assumptions here; one, that White is usually a stronger player and receives 0.5 komi, versus 6.5 komi as in an even game. Therefore what is being shown here is proper play; if Black deviates from this proper play, it is regarded as either rude, because Black is telling White "I am stronger than you, I don't need the knowledge of studying" or hopelessly naieve (Black is telling White "I have not studied this game.") Which is also considered rude, since then how could you have appeared before such a White?

Now, where did I hear this? Gee, I can't remember. But I'm pretty sure a pro told me. ganbarimasu!

As black, you're behind from the beginning of the game. As always when behind, you have to raise the temperature, so that the value of the komi is not so big compared to the values of the plays.

A diagonal opening dramatically lowers the temperature by limiting the potential of all the corner stones. So it's a mistake for black, but should be welcomed by white.

Therefore as white, you should always open in an adjacent corner to give black an extra opportunity to screw up and play diagonal fuseki.