I came across a technique in muscle media magazine, which unfortunately went out of business in the early 2000s. Although the technique existed before the article, it was the first time I had heard of it. I cannot find the exact magazine article but found similar articles. The second article is particularly relevant to the original article as it was written by Charles Poliquin, who co-owned the Poliquin Group.
20-Rep Squats Program: High Reps, Big Gains (bodybuilding.com)
Workout Systems: 20-Rep Squats | Poliquin Article (poliquingroup.com)
I suggest trying the workout mentioned in these articles, despite the comments about breathing squats. The workout is intense, but effective. The author of the article, Charles Poliquin, has trained 26 Olympic medalists, proving its success. Poliquin utilized this method to teach his athletes that they were leaving many reps on the table, just like most people. If someone disagrees with Poliquin's approach in this thread, they should provide receipts before their opinion is taken seriously.
If you give it a try, let me know what you think. I'd like to know if it was as shocking to you as it was to me when I discovered I never came close to trying as hard as I could
Why You Should Learn to Love the 20-Rep Squat Set | BarBend
this article also credits Poliquin.