After playing the move, Black commented (see that 'Clash' post for background and links to the game),
1...b5 develops the Queen, creates a spot for a minor piece, prevents e4, and claims space on the Queenside. Not bad for one move, eh!
Not bad at all, I had to agree. For my own part, I commented,
I spent a lot of time studying the position after 1...b5, looked at many different moves that adhered to classical principles, and finally decided that the non-traditional 2.a4 was my best shot. It solved the problem of developing my Queen and gave Black an immediate problem.
GeneM picked up that 2.a4 comment, and wrote,
I respectfully caution us against the casual habit of using the powerful word "principles" when describing chess opening theory that is based on deep experience with only the traditional start setup. I believe some of what we today call opening "principles" will eventually be exposed as being mere esoteric tactical considerations of the traditional setup.
Yes, it's the same comment I quoted in Make the Obvious Moves First, but I left off GeneM's further thought that
Your non-traditional early opening move 2.a4 might well obey an important opening priciple of pure chess, even if it violates what we all have sloppily or ignorantly been calling an opening principle based on our very narrow experience limited to only one start setup.
That remark caught my attention because I had exactly the same thought when making the move 2.a4. It reminded me of an 'Every Move Explained' article I wrote a few years ago where I touched on a concept called the 'illegitimate disruption of balance'. See 1927 New York - Alekhine vs. Marshall, especially the notes to Black's third and White's fourth moves, where I incorporated some heavyweight commentary by Alekhine, Kotov, and Yudovich, from The Soviet School of Chess (1958).
As I understand it, 'illegitimate disruption of balance' refers to a (usually subtle) violation by one side or the other of the positional principles underpinning chess. The term is found nowhere else on the web, but is so logical that I'm sure it exists elsewhere under one or more different names. Briefly summarized, it gives the opponent of the offending party a 'heads up' to look for an atypical response that also violates positional principles, fighting fire with fire, so to speak.
Later in the same chapter on Alekhine, Kotov and Yudovich give another example of 'illegitimate disruption of balance', without identifying it as such. It so happens that I posted on the game some time ago in Alekhine - Rubinstein, The Hague 1921. Here the disruption of balance was Black's wasted tempo on the third move.
The concept of 'illegitimate disruption of balance' is one of the most intriguing chess concepts I've ever encountered. To understand it requires a feeling for 'balance', which can mean either dynamic equality in a single position -or- the back-and-forth volleying that happens so often in chess, where both players attack and defend on each move. Extending this to 'disruption of balance' means that one side purposely provokes the other by breaking the equilibrium. This is usually by some kind of a premature attack, although I imagine that premature defense can be just as unbalancing. Finally, the adjective 'illegitimate' implies that there are also exists a 'legitimate disruption of balance'. How to spot the difference between 'legitimate' and 'illegitimate' would be one of the tricks of the trade for the discerning master.
What does all of this have to do with chess960? Since we aren't absolutely sure that all of the 960 positions are indeed balanced -- although the available evidence is pointing this way -- how can we know which moves maintain the balance or disrupt the balance?
While I don't know the answer to that last question, I do know that 'after 1...b5, I looked at many different moves that adhered to classical principles and finally decided that the non-traditional 2.a4 was my best shot'. Was this an accident or had I stumbled upon a chess960 example of Alekhine's concept? I'll be on the lookout for further examples.