One point I forgot to mention, is that once you learn a technique that works for you from someone that knows what he is talking about, stick to it and practice, practice until you commit it to muscle memory, you will gain a ton of confidence.
Not everything that you learn in those school will apply to your needs, we attended several of the top schools and used part of what they taught, we compiled the best techniques from each one and developed a training curriculum to fit the needs of the Marine Corps, to keep marines going to high risk areas safe.
But what's important is not to allow your hard earned training to deteriorate by not practicing.
I do that every Sunday.