I'm not gonna speak for him but if someone asked me to define intesity I'd say something like this:
Lets take a movement everyone knows how to do like leg extensions. If you go into the gym on your first day of training and do...let's say 80lbs. You rep out until you've reached positive failure-or at least what you consider positive failure since it takes awhile to actually learn to hit failure-you get about 15 reps. The next time you go into the gym you try just as hard with the same weight but you only get 15 reps again. Was there intesity? In your mind sure but you didn't progress, gave your muscles nothing new to work with. Now if you go in and you bust your balls don't give up and gete 18 reps you've done an "intense" workout. next time you should strive for more weight...in order for there to be "intesity" you must constantly be moving forward in some aspect of your training.
No thats not the way intensity is defined for these HIT'ers. The concept of intensity that these guys adhere to really is a
percieved intensity than the kind u describe- though ur definition is wrong (no offense), it still offers something that can be GAUGED, i.e. there is an element of progression; the idea that I will outperform myself from last workout, whether it is getting more reps or upping the weight.
So if you're feeling better than your previous workout and you outperform yourself from last time,
intensity as u described is increased by virtue of doing more even if perceived intensity may not have been as high.So basically IMO, "perceived" intensity is a crock of shit since it can't really be measured. Your workouts revolve around how "intense" they are supposed to be instead of how much weight is lifted (or repitions/sets performed with a particular weight).
A pound of weight is always a pound of weight. A pound of intensity....wait..