Now, most of the boxers and combat sports athletes Phil Daru trains had one thing in common before they met him; they were over-training or didn't understand the science behind high level ATHLETIC training, ultimately causing them to improperly train on a daily basis...
This lead to a SERIOUS problem in not only the performance of these athletes, seen in their speed, power, agility and endurance but they also began to have health problems due to their inability to recover and eventually dealing chronic injuries that weren't able to heal.
Overtraining or improper training basically creates a malfunction of the nervous system where you can't recover, explode or perform at your body's full ability.
As you can imagine, your reaction speed and timing has to be on point, there isn't any room for hesitation...When you have punches flying at you, you need to have your nervous system firing optimally, especially if you want to be able to counter your opponents punches with powerful shots.