Black is fatally "weak in the dark squares" - the sort of mystery pronouncement beloved of
people to whom such things are blindingly obvious! What it means in this case is that White
(to move) can tiptoe towards Black's King on dark squares, like one tiptoes around creaky
floorboards when trying not to wake a sleeping child. Try it and see what it looks and
feels like. Maybe such people know what they're talking about.
Click here to see the solution