Mindset is a third. If you don't have the basic marksmanship skills or have piss poor gun handling and crappy tactics, I don't care how good your mindset is, you will have problems. What I really take away from your post is "motivation". This is what drives Wayne and I in how we train. We train to the 100% goal for the type of encounters we are training to.
Trevor- interesting observation and keeping in mind this is on a course where you know ahead of time that you are getting. Imagine it as a surprise. You will definitely need a gear and focus change.
As far as what to do if it doesn't work. Keep working. The discipline will need to be to not kick the horse faster. We get students and even ourselves blow shots all the time. It is why we use that 100% goal...so we have trained to fix it and we know how to fix it. It is going to be a combination of sight focus and trigger press.