Trusting every video on YT for advice is the same as trusting every article on Wikipedia for expertise, accuracy, and truth. Sadly, I fear the majority of folks do not realize the folly in either of those positions.
No information on what sort of doctor he is, what formal training in firearms he has had, or how few competitions he has been in (See below).
Herbie says (below) he is a firearms enthusiast; enthusiast does not equal expert.
Rodney said he watched only this one DrTactical video; I believe DrTactical watched only the one ASP video he commented on.
On his channel we learn, "DoctorTactical, AKA Dr. Herbert Mendelson, AKA Herbie, the founder and owner of the 'DoctorTactical YouTube Channel,' is a firearms enthusiast who loves to discuss and share information with everyone and anyone who shares his passion. He is a competitive shooter (which means he has entered some competitions...if his love for guns could only translate into great shooting talent, he would be one of the top shooters on the planet... but sadly, it does not). "
His site at doctortactical.com is nothing more then a merch store; anybody want a t-shirt or travel mug?