The question, then, is whether persistence is an act of pure will, or whether it come form personal disposition. Sorry, I don't have a full answer for that. But I believe it is mostly the latter. To illustrate, let me switch from the word persistence to a different word, compulsion. Both imply stick-to-it-ness. Compulsion implies even more, an inability to stop. What happens when what Ericsson call effortful study becomes compulsion?
And with that question let me move from what is pretty solid social science to a different arena, one that some believe is truth but others think is closer to voodoo - personality typing. I'm particularly thinking of the typing scheme called Myers-Briggs. I've been tested in that schema several times and almost always am measured as an INTP. If you follow that link, see if you can see an element of compulsion in the definition of the type. Also see whether it seems like it is descriptive of me. Incidentally, when I've measured differently it is on the first characteristic, which can either be I (introvert) or E (extrovert). My job demands the latter so sometimes I embrace those characteristics, but I do believe it goes against my type. I'll let you do your own google search on this stuff if you are interested. All I'll supply here is the acronym MBTI for Myer-Briggs Type Indicator. There are sixteen possibilities, based on four basic binary characteristics.
If you believe the story, INTPs persist in an effort to understand truth as their raison d'etre, but once they've achieved that they drop the idea like a hot potato and move on to the the next thing. This makes us great planners but really lousy implementers and it may be a reason that I really admire those who persist well into implementation, because I can't do it well, my calling is elsewhere.
Let me change gears one more time and talk about the difference between expertise and genius, Howard Gardner calls them Extraordianry Minds. This book is probably a bit too much right now, but if you are looking for a diversion, you might enjoy it. He spends some time up front distinguishing between precocity (a la the Suzuki method for learning a musical instrument) which is in some way predicatible, otherwise how could the method be effective, and genius, which is not predictable at all. He also discusses the Terman Study, and that early measured high IQ has limited predictive power. The people who he does focus on, the extraordinary minds, are all familiar to you. The nature of their genius, however, might be novel.
Genius is certainly an absorbing subject, but it does take us far afield from effective change, where we hope that is possible even for us lesser mortals.