In regarding to high FOC having a negative effect plays in part of stability of the shaft. If your shaft is not rigid on impact all that "tip weight" transfers essentially into the shaft that misbehaves like a pool noodle. This is why a .166 shaft can become a negative in some cases where shooters have a bad experience on game running high FOC on .166 shaft.. The large dia shaft can have more structural integrity not only on impact, but on recovery from the launch. It recommend to listen to the other podcast to grasp some of it as a whole.
The Concept System while it can have benefits to have better overall dynamics with lesser FOC it can also maximize the use of higher FOC.. If building with concept tube and SS double shoulder insert there is a 150gn up front not counting shaft weight or point , and it's through the front several inches of the shaft which makes the shaft more stable.
Rod White Olympic Archer did testing on an arrow he built called the "boom stick" the arrow was based on a BE Rampage Shaft with Concept system and aero vanes. He shot it against all other arrows of the same weight, leaving the bow at the same speed and the result was the Boom stick yelled over 25fps down range at 50yrds ,, where it is needed vs the archery industries highly advertised "launch speed" sales pitch.
In my testing of POI ( Point of impact ), not in terms of accuracy to hit bullseye
The factory Zombie slayer arrow and 1.0 Concept system were of the same approx weight and shot the same zero at 25 yrds holding the same cross hair. The 2.0 Concept system arrow being heavier by 25gn shot a lower POI at 25 yards by about 2 inches.
At 50 yrds the 1.0 yielded approx 1 ft higher POI,, the 2.0 came up approx 6 inches higher POI making up another 2 from the lower POI zero in.
At 120 yrds the 2.0 Concept build came in at approx 24 higher POI than the factory,, the 1.0 went completely above off target so adjustment had to be made to make sure both arrows were on the 48 inch target.