Why the Thach Weave used four fighters in two sections

Thach's formation divided four fighters into two sections, each consisting of a leader and one wingman. Before the war, the two-aircraft section was considered too radical to impose across every squadron, although he received permission to use it in his own. Other squadrons began abandoning the third aircraft in each section without necessarily adopting the weaving manoeuvre. James Flatley proposed trying a six-aircraft formation alongside Thach's four-aircraft arrangement. In Thach's recollection, Flatley later reported that the extra pair became lost and endorsed the four-aircraft division and the Thach Weave for fighting superior enemy aircraft.