So much the better. Systematical comparing with the regular Exchange should answer your question. I have noticed one advantage of the early a2-a3. Lines with Nb8-a6 are pretty pointless. So at the moment I think simple development of the King's Wing is Black's most straightforward equalizer. There might be other, more ambitious options.

raspoutine wrote on 07/30/09 at 16:34:17:


Either this is a typo and you mean "Black" or you are happy to equalize with White after 7 moves. 

Before the sequence Bd3 dc4, the little waiting game occurs quite often: a3, Re8...

I wouldn't say it bamboozles the evaluation, which is: Black must still get out his bishop.

No need to exchange anyway, a3 is useful in the Orthodox 

This one you should be able to answer yourself, don't you think?
1.d4 Nf6 2.c4 e6 3.a3 d5 4.cxd5 exd5 5.Nc3
a) 5...c6 6.Qc2 Be7 (g6 7.Bg5 Bf5 8.Qb3) 7.Bg5 0-0 8.e3 and I don't think a2-a3 is more useful than Ng1-f3 or Lf1-d3. So 8...Bg4 must be good enough.
b) 5...Bf5 6.Qb3 Nc6.

Its going to be hard for Black to "prove" that a3 is a horrible move.
Because it isn't.   It's a useful little move.
But it's also clearly not the best use of the tempo.  

I don't see that Black is can be any worse after 3...d5 with typical QGD stuff where White is effectively a tempo down (or "half-tempo").  
White isn't worse, and black needs to be sensible to this. 

I remember Mickey Adams describing 1.d4 d5 2.Bg5!? this way.
Basically, its completely playable since White isn't worse, but most strong players would be happy to see it as Black since they don't need to fight so hard to equalize. 
I think the same applies to this 3.a3  

raspoutine wrote on 07/26/09 at 03:01:20:


But White can't spend a tempo on an early a3 and then expect to reach a standard Exchange position.  Black might exploit this by getting in ...Bf5, for example.

HoemberChess wrote on 05/13/09 at 10:35:31:


I take it then that you are not a subscriber? John Emms featured 3 a3 in his April 09 update.

The late great Tony Miles once played 3 a3 in an important game in the 1979 Riga Interzonal against Ribli - and lost after Ribli got an easy game by playing 3...d5 and then transposing into the QGA. But funnily enough when Miles had to face 3 a3 with Black three years later in the Vancouver Open he chose 3...c5; this could be the famous "fear of improvement syndrome" but more likely he wanted something sharper against a lower rated player in an open event, where winning with Black is more important than it is in an all-play-all or a match.