Good job, BRatliffe. The before (race plans), during (race craft) and after (analysis) all play into this. History is a great teacher, and consciously or subconsciously play a part in all three aspects.
It's no secret that most of my best performances since returning to racing in 2011 have been as solo efforts off the front. The beginning to the middle of these kinds of efforts involve all the things discussed in this thread, both physical and mental. The race craft and physical preparation enables the effort, the mental strength along with the calming effect of the adrenaline strengthens the confidence and the will to win. But at some point, the adrenaline wears off, the power drops, my lungs are exploding, and the focus of the mental piece switches from confidence to fear. Fear that all of this effort will be a waste. Fear of the "storytelling" that will come afterwards. Fear of failure. Fear of not living up to your expectations. Fear of letting down others that may have worked hard for you. Fear of quitting this sport for a second time. Fear can be a different kind of motivator. For me, it's the last step before the abyss. Nothing gets me to dig deeper than fear. Losing Somerville in 2012 was one of the best lessons I have ever learned in cycling. I was not solo, but all of the above applies. Those last three laps when I was taking half lap pulls with a 15 second break was 100% fear of getting caught after almost the entire race off the front, and I couldn't finish it off. The immediate reality was mentally crushing. It affected my racing for weeks. Mentally I went to the edge, and with some help, pulled myself back. I could have quit right then and there. I went on to have a very good season by any measure. My point after all this is that fear, consciously or subconsciously, for whatever reasons one may have, is probably a factor for every athlete no matter what sport or level of competition.