If you don't mind I'd like to ask for some advice. I've been playing the Aronin-Taimanov variation against the Kings Indian quite some time (since I started playing chess again...about 1.5 years ago), and it works quite well in the 'normal' competition and tournaments (I only played about 4 or 5 games with it though)

But now a club player has taken up the King's indian and I played one game with him since then and really had to fight for a draw!

Now I started studying it a bit again and almost became afraid of all the lines white can't play and black has possible.

Well, theoretically speaking white is doing well in many of the lines here. 13...a5 has been regarded as best against 13.a4 and then a lot of theory follows. What is subject to debate though is whether (after 13...a5 14.Nd3 b6) the immediate 15.b4 or the preparatory 15.Be1 followed by h3/Nf2 is better. Gallagher, in his highly regarded book "Play the King's Indian", regarded 15.b4 as more dangerous for black to meet and said black is fine in the 15.Be1 line citing the game Nielsen-Kotronias, Hastings 2003. However, if one actually studies that game in detail, especially with the help of strong engines such as Fritz and Rybka these days, then one will realize that there are a number of improvements for white in that game that can allow white to play for an advantage.

All that said, the Classical mainline (Mar del Plata/Aronian-Taimanov), is definitely not refuted and is perfectly playable. The reason why it is not played more often by the very top GMs is probably due to:

1) Fashion

2) They regarded the Bayonet (9.b4) as more problematic for black to meet because the Bayonet offers white similiar kinds of attack like the classical mainline while denying black his usual kingside counterplay. That means the Bayonet is less risky. But this is before Radjabov's KID performance in the recent Corus tournament. :)

Anyway, the Aronian-Taimanov/Mar del Plata/classical mainline has a lot of theory and is a complicated line that leads to very double-edged positions. Im most cases, it is white who has to be more cautious in this line because one mistake can lead to a checkmate from black (that's the benefit of attacking the king) while one mistake from black does not necessarily end the game. So if you really want to continue to play this line then you must make sure you have a very deep understanding of it and have a good memory memorising many of its theory. Studying the games of Korchnoi and Nielsen in this line will help too.

Eric I was just wondering:

Personally, i used to play the 13.a4 variation, but in this particular position now prefer 13.Rc1, as i feel it gives White more of an initiative. Players i have faced also seem to have more of a problem against it than the 13.a4 line.

I suggested to Susan Polgar at her blogspot that she (or you) contact NTD Tim Just in search of an answer for the young lady who is blind and playing chess.

You've known Tim for a lot of years.

Tim runs the USCF Blind Championship each year.

Hope this helps!

Peter / chesstoplay