This book takes a closer look at the Classic mistakes by amateur players
include: 1. Moving a piece too often in the opening. This is one of the
mainstays which we think relates at least partly to the desire to create
something in the opening, when we would be better advised to focus on simple
development. 2. Impatience. Sometimes amateur players are too eager to change
something when there really is no need. 3. Overgeneralizing. One of the biggest
differences I've noticed when comparing professional play to amateur play is that
the former is much more about concrete calculation - you go there, we go here
and so on - whereas an amateur player will have a tendency to overgeneralize
when thinking about a position, perhaps because they are not used to the basic
art of calculation. 4. Cutting variations off too quickly. Amateur players do
not extend their calculation far enough, and thus superficiality tends to kick
in. These and other mistakes are explained in the book. Of course it
should be noted that professional players also make these kinds of mistakes.