Outside Critical Square--Part 2
As mentioned previously the critical squares for a pawn on the 2nd, 3rd, or 4th rank are two ranks ahead of the pawn. So in the diagram below the e4 pawn's critical squares are d6, e6, and f6. We also mentioned that the outside critical square, that is the square farthest from the enemy King is our target square for occupation. If the superior sides King can occupy a critical square on the 6th rank, in front of the pawn, it's a won game.
A major mistake would be 1.Kb3 which allows 1...Kb7 and Black takes the "Distant Opposition" keeping the White King from reaching the outside critical square f6.
The correct plan is the "extended overpass". White plays 1.Kc3 and makes a beeline passing in front of his pawn, to occupy the outside critical square f6, unobstructed by Black's King.