The timing of the attack, assisted by the weight of the attackers body behind the weapon, creates the concentrated force that allows the point to penetrate with ease. The swordarm is straight but not locked allowing the force to go out to the point. To hold the rapier with the wrist, elbow, and shoulder locked, like a battering ram is incorrect, and would produce a recoil effect. Diestros A and B stand at opposite ends of the diameter. To insure a safe position Diestro B responds by moving and maintaining the diameter.
Red line is the new diameter.
Diagram II Diestro A stops at point C while Diestro B continues moving, thus creating the opening for Diestro A to attack at an angle. Red lines indicate the acute angle. Diagram III Diestro A's rapier travels at an even more acute angle toward Diestro B. A's rapier controls B's blade by opposition as it travels forward to B's face. At the same instant B steps slightly to his right and lowers his point toward Diestro A's face. Diestro A impales himself by the force of his own attack.