Dear MichaelG:
Believe it or not, I actually agree with you, with one exception.
Your instructor screwed the pooch big time. He should have his ticket yanked. Enough said about that.
My other comments were not directed towards criticizing your performance. I suppose that it counts for something that you got out alive. That fact that you may not have known better goes to your training.
I believe you when you say that you knew the risks. What you don't know is how to manage the risks, which is why I suggested additional training from a different shop. I'm not suggesting that you need to learn fin pivots or mask clearing. Instead, you need to learn dive management. A good shop will teach you how to evaluate a dive, minimize the risks associated with the dive and, when those risks cannot be properly managed, to say "NO".
I tried to make my posts detailed for because I wanted to establish the basis for my suggestions and not simply sound off. I also wanted to suggest an alternative method that might help in the future. For what its worth, what I posted is how I dive.
I agree that you did not ask us to feel sorry for you. However, it is important that you recognize your role in the situation or you will be doomed to repeat your earlier mistakes.
My one disagreement is that I have no problem blaming the shop, the instructor and whoever certified you in the first place. You were not sufficiently trained to manage the dive or the danger you faced and you were left hanging. That is unacceptable.
BTW, I am not a professional diver. I am simply another diver with an opinion based on training and experience. If I am wrong, then I invite correction. In the meantime, I stand by my position.