1. Gyro Trac offers a low flow head, maybe FAE did the same?
2. Super Trak makes a High flow Takeuchi TL150, so maybe that is a Super Trak machine?
3. From the sound of it, that thing could barely chew it's way out of a paper sack! I could have chopped up that little tree ten times faster with a bush hog on my T-190. Or even my old school bush hog and Yanmar tractor! So my third guess is maybe the guy doesn't know you need a high flow machine to run that cutter?