BPaulsen wrote on 02/13/10 at 13:09:27:
A normal opening advantage does not exist. Period. White can play moves that are alright and still not obtain anything. A lot of openings cease to be critical because they do not offer any advantage.
To clarify what I mean, I would consider a normal opening to be one that has commonly has grandmasters playing either side of it. I would further consider that all these opening have fairly similar evaluations, i.e. White has decent chances to get an advantage and Black has decent chances to equalise. E.g. the Spanish and QGD I would consider to both be better for White, regardless of whether theory states that Black can equalise or White has an edge because White is always the one pushing for something. So this week it may be += or = but you can consider a sort of average to be +==.
I then use this a rule of thumb when evaluating unusual positions, e.g. this looks like opening x, but where Black has done y, which he wouldn't normally do in opening x, therefore White is better. In this case I would consider that both players have done something that they wouldn't normally do, so as a first approximation they can be considered to balance and so the evaluation reverts to the default.
Of course this can be wrong, but most opening positions are so rich (unless someone has done something badly wrong) that proving an evaluation can take many games over many years and even then it can still be overturned.
If you look at an opening like the Latvian it looks iffy on general principles, but it's taken a vast amount of effort to reach the current point where it's almost dead (and it's still not nailed down). Would you really want to have to go through that process every time you came across a position that looked a bit Latvian-like? Or would you prefer to say it looks like a Latvian so I'll assume it's good for White until proved wrong.
Anyway the sense in which I use normal White advantage simply means worth playing for White.