I understand what Professor X is saying, but I didn't think of 10X3 as being heavy (not relatively very heavy anyway) since you're using a load that's approx. your 6 rep max.
Going to failure with your 6RM you might traditionally get 4 sets that look like this: 6, 5, 5, 4, and that's on a good day and you'd possibly be burnt out or exhausted. With 10X3 with your 6RM you'd get a total of 30 reps and you feel like you can do more, where you'd get only around 20ish reps with sets going to failure.
Just don't forget that with Chad's routines, he's suggesting a gradual increase in volume and of course starting out with a volume that you can handle, that is why so many people have success with his ABBH program; it's relatively low in volume.
People continue to have success with Chad's routines because the order that he recommends them in has a gradual increase in overall volume and you're constantly using many different compound movements.
Constant change (but not too soon) and continued increase in volume with fairly heavy compound movements mixed with lighter movements is almost guaranteed to get hypertrophy and strength gains and allows for central nervous system recovery if done right.
Also, don't forget that Chad (and any other coach writing an article here) writes them for the average person where the most people can benefit from them. They are not specifically designed for any one particular person so some adjustments may need to be made.