What youre asking for is very difficult to obtain.
I believe theres an FUE study showing the difference in transection of sharp vs dull punches by Dr. Shapiro tited "A Side-by-Side Study of 20 Consecutive FUE Patients Comparing the Use of a 0.9mm Sharp vs. 0.9mm Blunt Punch." The yields are vastly different. There are many many different variables for FUE hair transplantation and we dont know which (if any) are confounding variables. Punch type (Sharp, serrated, trumpet, etc), manual or motorized, punch system (oscillating, one direction, ultrasonic, etc), motorized punches have all kinds of settings that can be changed, technique of removing fue grafts (there are many that utilize different types of torsion and traction), donor characteristics of each patient such as the curl of their hair root and thickness of the roots. Implantation method can also affect the graft survival. Is the doctor using stick and place, forceps with pre made incisions, implanter pens, etc.
On the other hand the extraction part of FUT is very straight forward. A strip is taken out and dissected under a microscope. Many of the issues are moot at that point.
When hes referring to quality level, I believe hes referring to the quality of the individual grafts obtained. Its well known the quality of FUT grafts are going to be good. WIth FUE there are many physical forces involved to remove them (traction, torsion, friction, etc), all of which are not good for grafts. But if the grafts are obtained by a doctor who knows what hes doing with FUE with the right patient, then according to him, the grafts will be equal in quality.
With FUT you are taking from the safest area of the donor area- right smack dab in the middle of the occipital, parietal, and even temporal areas. With FUE you have to scatter your extractions out to get a higher number of grafts and you are going to be going out of this "safest" zone of hair. Therefore, by removing as many grafts as you can with FUT (with consideration of the donor hair characteristics and elasticity of the scalp) then moving to FUE to remove hairs scattered around the other zones, will naturally yield the most hairs.