I've know John for a decade or two. (Hesitate to estimate, as I get older, time flies even more)
We first got to know each other, I believe through internet forums, and then met in person at RenEx conferences.
As you'll hear, John has a wealth of information and practical experience as an exercise instructor.
Some of the highlights from this conversation include the need to limit variability contrary to the concept of "muscle confusion" espoused by some.
Also, very interestingly is John's focus on "progression" as much or more so as a matter of continually improving behaviours in order to create greater and greater stimulus, by always making detailed improvements in form, distinct from just progressing in number or reps or poundages used.
As such, John is fully embracing the "real objective" vs the "assumed objective" of proper exercise