Especially for your bigger lifts, those important ones we just mentioned, they need to be based upon your results that you found in your Gauge Workout.
The reps and sets should alternate on a nearly weekly basis always taking into account the load you're aiming for. You’re still lifting the same equivalent weight, but the reps and sets you’re using provide the muscle with a different look.
That’s one of the limitations of programs that focus only on a single rep count and an arbitrary chosen weight that usually takes a few sets to actually figure out, all the while fatiguing the muscle while you're throwing darts in the dark trying to find a weight that's just right, when you really have no clue what just right is.
When you're told what weight you should mathematically be lifting, your workout intensity doubles because you've been shown what you should be lifting (it's usually a higher weight than you'd guess), so you push yourself that much harder to fulfill the calculations.
Not only are you lifting heavier weights because you're pushing yourself to get stronger, but you're busting your ass trying to fulfill what the percentages have told you that you should be lifting.
My workouts more than doubled in intensity when I started using percentage-based training, and I thought that bringing math into my workouts would ruin them!
Fortunately, I was wrong!