I really have to disagree with most of this. First, set/rep schemes for growth tend to be individual in nature. In general terms, however, the “older” your lifting age is the fewer reps you need for hypertrophy.
I grew well when I went to a 5X5 workout. Then I went to a 10 X 3 and did well. Now I lift as a powerlifter and continue to grow, although I use mostly singles and doubles.
Second, I also disagree with using 3X10 to “learn proper form” When using higher reps form has a tendency to break down more due to fatigue and lack of focus. I agree in using lighter weights to teach form, but only until the form is learned. Otherwise, once again I recommend heavier weights and lower reps.
Third, the “10-8-6” pyramid is really pretty outdated. It can be effective to a point, but it’s not the best way to go. Stay away from the Muscle & Fiction advice.
First, I made the assumption that he has a relatively young training age, which is why I recommended 3x10 at first. He can eventually progress to 5x5 and 10x3. I didn’t say he has to stop at the 10-8-6 pyramid.
Second, it’s easier to learn proper form using 3x10 than 5x5, especially at a young training age. It allows you to practice reps more often with lighter weight, and this is good for motor learning and efficiency.
It’s good to drop your ego and lift your 10 RM with good form, even if it means training light. Once you master proper form, strength should come very quickly when you switch to more intense programs.
However, if he turns out to have an older training age than I assumed, then he should stick to lower reps and higher % RM’s than I suggested.