Most athletes respond best to a high frequency and high volume of weightlifting, and perform best when not handling maximum poundages at each session.
The Heavy-Light-Medium training system gives the athlete the volume and frequency that they need to drive progress, and ensure ongoing success, while allowing enough recovery for one heavy day each week for maximum output.
The benefit that this program has for athletes cannot be overstated. Non-barbell sport athletes must balance training for their sport and training in the weight room. Most sports are demanding of the lower body and many athletes will not have enough reserves in their tank to squat heavy more than once per week. The HLM system allows the athlete to place their heavy squat day on the day of the week that allows them to train in their most recovered state. During the rest of the week, the athletes will have to perform strength workouts, by and large, in a state of fatigue. The HLM system makes this a little easier to manage. On the light and medium days, the athlete will be focusing on form and technique, and speed.
As a starting point though, start your light day 10-20% lower than your heavy day, and set your medium day 5-10% less than your heavy day.