I didn't mean to be quite so gloomy! 4...a6 seems to have stood up well lately at the top level and somehow it's hard to believe that 5 h3 can be a completely deadly reply. Another quick thought - 5...Bg7 6 f4 e6!? (Tkachiev's method a move early) delaying castling would allay my fears about a quick hack. In the Hippo the knight would prefer to be on e7 than f6, but maybe Black can play ...Nc6-e7 next? At some point over the next few moves White must decide which side to castle...
5 a4 is obviously reasonable, but it can't be critical in the sense that it gives Black the information he wants: White's king is going to the kingside. 5...Bg7 6 Nf3 0-0 7 h3 Nc6 is not the only possible path, but it transposes to what I've called the Accelerated Classical.

Fascinating stuff. I got briefly interested in 4...a6 when writing 'The Pirc in Black and White', but felt that the reply I give there - 5 h3 - was very strong. Main idea: 5...b5 6 e5! The great Pirc guru Peralta has recently won with this as Black - after 6...Nfd7 7 Qf3 Nb6 8 a4 b4 9 Ne4 Bf5 (9...Be6!?), with complications. But I don't trust this and a Black player who wants this kind of position should perhaps take up the Alekhine, not the Pirc... Instead of 8 a4, maybe just 8 Nge2 - White waits for Black to castle and plays Qg3, h4 and after ...h5, Nf4xg6. Black is allowed some moves too(!) but where are his pawn breaks? - that pawn on e5 is quite strong.
So we may be left with this: 
Petrik-Tkachiev, Dresden 2008
5. h3 Bg7 6. f4! O-O (better than the 6...b5 I gave in my book) 7. Nf3 e6 8. e5 Nd5 9. Nxd5 exd5 10. Bd3 Nc6 11. c3 dxe5 12. fxe5 f6 13. exf6 Qxf6 14. O-O Bf5 and Black was ok and won this game too. But White has more promising tries here - 8 e5 looks rushed and 7 Qf3 is possible. As I showed in notes to the game Aagaard-McNab, the Hippo against the Austrian Attack (which is what this now is) is quite dodgy. Again: playing neither ...c5 nor ...e5 leaves Black open to a route-one attack with g4 and h4.
Those are my first, non-engine assisted thoughts. But Tkachiev and Kramnik may have seen something I missed  Any guesses?

My interest in the Pirc has been completely rekindled/transformed since I realised recently that it was respectable for Black to meet 4 Be3 with [u]4 …a6[/u]!?, as played recently by Kramnik, so I thought I’d start a thread on this! I can’t seem to see much theory on this (not having yet got hold of a copy of [i]Pirc Alert[/i]!) so I’d be interested to hear what folk think are the critical lines. The main line must be [u]5 Qd2 b5 6 f3[/u] (6 Bd3 could transpose to V below) [u]Nbd7[/u] (some strong GMs have played 6 …Bb7 and there’s also 6 …c6), and now:

I  [b]7 Nge2[/b]. Now transposing to a Modern with 7 …Bg7 has been much the most popular recently but Kramnik played 7 …Nb6.

II  [b]7 g4[/b] Nb6 (7 …Bb7!?) 8 g5 and White has done well – is this line a serious threat?

III  [b]7 a4[/b] b4 8 Nd1 Rb8 (also 8 …a5 and others).

IV  [b]7 0-0-0[/b] and now 7 …Bb7, 7 …Nb6 and 7 …c6 have all been played. Is there any consensus on the best line(s)?

V  [b]7 Bd3[/b] (looks less critical?) Bb7 (also 7 …c5!? – see the nice game Caspi –Tseitlin) 8 a4 c6 or 8 …b4.


Of course White has other seventh (and earlier) moves, but overall, I get the impression there’s lots of scope for fresh ideas here and plenty of discoveries waiting to be made …