2.5. King and Two Pawns versus King and Two Pawns
Although more material generally implies a widening of the scope of strategic and tactical ideas, these endings still belong to the simpler kind of endings; the choice of the plan is mostly determined by the elementary positional principles with which we have already become familiar. Due to material equality these endings are drawn most of the time. The positional superiority plays a principal role. This positional advantage is expressed not only through the more active king position but also depends to a great extent on the pawn structure and the distance of the pawns from the promotion square. It is here that we shall get acquainted with the characteristics of the doubled pawns, the new strategic element – blockade, the tactical element – breakthrough, as well as the more complex forms of defence by stalemate. With regard to the crucial importance of the pawn structure in choosing the plan and strategy, we may divide these endings into three basic groups: with passed pawns, with one passed pawn, with no passed pawns.
2.5.1. Passed Pawns
In endings of two passed pawns each, the outcome depends on the three basic factors: the pawns’ proximity to the promotion square, their mobility and relative king position. As we have seen in the chapter King and Two Pawns versus King, isolated pawns are, as a rule, more powerful than connected pawns since they can “overstretch” the enemy king by a joint action and reach the promotion square more easily. We shall first examine the simplest case with connected pawns. The following diagram is a study by B. Horowitz, published in 1879.