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But Master_ Valek, e5? is a mistake, according to this book. This is due to 7. dxe5 dxe5 8. Qxd8 Rxd8 9. Nd5: so Black can't play e5 there.
I'm sorry, I was so surprised that there were so many people commenting on my forum, that there was a second page of comments, so, yeah, that's why I didn't see Doduobird's comment.
Black can play ...e5 against the Averbakh, he just needs to prepare it first, usually with ...Nbd7 and ...c6 to avoid any unpleasantness with the pin. But he still won't get the easy normal KID counterplay with a quick ...Nh5, ...f5 & etc.
Again: it's not some crushing position for White, maybe a very slight edge but nothing to brag about. The point is taking Black out of his comfort zone.
Actually, Master_ Valek, 6... e5 loses to 7. dxe5 dxe5 8. Qxd8 Rxd8 9. Nd5! (double attacking the knight on f6 and the pawn on c7). This is why some players play 6. ...Na6 or 6... Nbd7 first.