Late last week I simultaneously received copies of the latest issues of Chess Life (August 2011) and New In Chess (2011/5). Oddly, both had articles discussing chess psychology.
In Chess Life, it comes in Andy Soltis's Chess to Enjoy column, "Blunders Happen". Soltis claims that most players suffer over past blunders, but masters just accept them as part of life and move on. Masters, however, have their own psychological cross to bear: regret over missed opportunities. After offering several ancedotes purportedly showing how such regret affected great players afterward, he offers an application anecdote:
Regret can have such a psychological effect that it's been turned into a weapon. Bent Larsen recalled the "very good trick" he used when he left a pawn hanging against Oscar Panno at Palma de Mallorca 1969. Panno, in time trouble, didn't take the pawn. Larsen replied very quickly, protecting the pawn. "I make [sic] him think he should have taken it!" he told Overboard magazine in 1974. Panno's position quickly deteriorated and he lost.
A nice story - especially if you don't bother checking the details. You can find the game here, and the key sequence is 28...Bc3 (attacking the b-pawn) 29.Rg3 (sacrificing - or hanging - the pawn) 29...Qf6 (declining the offer) 30.a3 (protecting the pawn). So what's the truth? We'll discuss it in two parts.
First, Black should have taken the pawn - though it's not hugely better to do so and Panno's caution in time trouble is understandable. Larsen was right to protect it next move, and the position was about equal.
Second, there was no quick deterioration. Panno was in time trouble and Larsen was one of the world's absolute best players (top 5 for sure), so it's hardly surprising that Larsen went from equal to slightly better by the end of the time control at move 40. But that's it: slightly better! If Panno played 42...b6, White's edge would have remained a small one. The position was tricky, though, and Panno blundered on moves 42 and 43 to lose. Chalking this up to a psychological trick on moves 29 and 30 seems pretty improbable.
The second example, from New In Chess, shows up in Luke McShane's review of Lessons with a Grandmaster by Boris Gulko and Joel Sneed. It's from the game Taimanov-Gulko, Moscow 1976 (replayable here), and the psychological moment comes with 19...h6, which Gulko awards an exclamation point. Here's the dialog in the book between Joel (the amateur) and Gulko:
Joel: Why did you give this an exclamation point?
Boris: I continue my psychological battle. I am defending against threats that don't exist to give the opponent the impression that he has the advantage.
Joel: But 19...h6 seems very natural. You neutralize the threat of h4-h5.
Boris: But h4-h5 is not a real threat! I could just take the h-pawn if I wanted to. However, I defend against h4-h5 anyway. If Black is on 'defense', White must be on 'attack'. Because o fthis impression, White played an unfortunate 'active' move.
At this point Taimanov plays 20.Re1-e4, and after 20...b5! realizes that the rook does nothing there - there's no attack after all - and rightly brings it back: 21.Re4-e1. A subtle trick by Gulko!