I train my own dogs. But I am not a professional. I've had professional trainers that are my mentors in this space for a long time to guide me through some situations. But other than that I do the work myself.
One of said mentors is a dobbie human. Probably the best with working dogs I've ever met. She can figure out the "why" and "how" to address in just a few minutes of observation sometimes over a short video clip.
My pops was a professional breeder of german shepherds for many years when I was a child. I know that breed well (the working ones and not the show lines).
If you were getting one, would you stay with doberman or a different breed?
Is there a difference between GSD and Alsatian?