The aspect I teach comes from the phenomenon of Who's the Barber, here?
Please watch the video and you'll see what I'm talking about. The moral of that story is that divers will inevitably run into instructors that will tell the student, "I've been doing this for 30 years!" ...and because of this, you shouldn't question what I'm telling you.
We've all seen those divers that we can't explain why the are so bad, and I'm guessing it's from following orders or copying what they're seeing. Diving equipment has changed tremendously, instruction is different, and lastly standards have changed. Anyone telling another that their skills, advice, and abilities from 30 years ago should supersede today's or common sense, needs to find another instructor.
Yes, it's not always this black and white, however, I'm training divers to become autonomous and once I've cut that proverbial umbilical cord, they have to be able to make decisions without the assistance of the instructor; me... If they can't do that, are not willing to do that, or believe that the instruction they may get elsewhere will never do them wrong, then they're not ready to be on their own.
Sure, this is subjective but if something doesn't look or feel right, IT'S NOT RIGHT for them...!!!
There are times when an instructor has to push a little more to get the reluctant student to get to that next level, but anxiety from the student shouldn't be a roadblock, it should be a speed bump that tells them to slow down... It's not something they can't do, but something that will make them a better diver because they won't put themselves or others (including the instructor) at risk.
Anxiety can be learnt to be dealt with. Stop, Breathe, Think, and Act. If panic sets in, there's nothing that can be done except to bolt to the surface. We must fix the issue first, where their at -- underwater. The surface is their final destination.