WOOO,
How so is it hogwash (or maybe I am misinterpreting your comment?)
As a competitive cyclist, I have trained long duration (>3 hours) at pulse rates of up to 155 out of a 195 max pulse. I have also trained short duration (1.5 hours) at an average pulse of 175 bpm/195. In one case I was training for 100 mile events. In the other it was for criterium racing which emphasizes great speed and acceleration at distance of ~30 miles.
I have documented this in my training logs, using an SRM powermeter with real time data collection that I downloaded after each session. I weighed myself daily just after rising.
When doing the high intensity work (1.5 hour sessions), my fat levels stayed very constant and I didn't see any steady trend towards lower body fat over the months I was doing it. I maintained a great deal of muscle mass, competing in cycle races at 185-200 pounds (at 5'8")
When doing the low intensity long duration work, I got as low as 155 pounds, and my skin got nearly paper thin. I also had no muscle mass to speak of!
I have tried other regimens for different purposes, including Tabata's original protocol designed after his work with the Japanese Olympic speedskating team. If you use Tabata's method, you will be exhausted after less than 10 minutes. Tabata suggests you do this 5 days a week. I lost about 5 pounds in a 4 week protocol of Tabata intervals. I also got very weak. I don't recommend this routine for extended weight loss. You will get sick.
In my competitive cycling career, I eventually settled on long slow distance (also called LSD training) in the early season to drop weight, and switched to short high intensity training in season to build up speed and power. It worked well.
The 4 words per breath measure actually came about after the work of Francesco Conconi (who came up with the anaerobic threshold concept). That simple test correlates very well with the onset of the 4 mm (millimoles) lactic acid threshold, where the body begins to go anaerobic (more or less). Below 4 mm you can train for hours. Above that you find your workout times become progressively shorter to exhaustion.