Hate to say it but natural talent isn't the deciding factor at all. The research shows that hard work and deep practice coupled with opportunity and good coaching makes world class performers.
Although it's much more romantic to believe that some people are more "gifted" than others rarely is there actually a conclusive test that proves it. Most of the time when the people who are supposed to have more talent are researched it turns out that they in fact had more training and deeper training.
Desire seems to be a key factor though. Two people who get the same opportunities with one of them really having a burning desire to get better results most times in that one actually becoming the better performer.
Physical limitations excepted of course. Your 120lb guy is not going to become an NFL linebacker because he desires to.
This is the age old nature vs nurture discussion we are having in this thread. There is no conclusive test that proves its one over the other, as you have stated. There may be a research paper that you read that favors one over the other, but this debate will be going on forever...
The romantic part of it I actually see the opposite viewpoint that you do. I think its "romantic" for a person to tell themselves:
"I can be that good, if I just work at it by doing xyz. But I have other priorities in my life. We are all created equal".
The other side of it is: "I'm not as talented as that person, no matter how much I work at xyz, I will never make it to their level. We are not all created equal"
In my view, it is easier for a person to swallow the first quoted sentence, not the second. The second sentence makes the person feel inferior. Even in this thread, there was 2 pages of posts before someone mentioned talent. I feel its just a way for a player that never had or can have it, to justify to themselves that its not a lack of talent that is holding them back, but just a lack of practice/competition/desire/etc.
Lets look at two extremes of pool players: Thorston and McCready. Throston grew up with coaches, lessons, structured practice, tournament competing, etc. McCrready grew up gambling his brains out. He probably never head a lesson in his life, or a practice session. (I don't know this as fact). Thorston has a fundamentally perfect stroke and stance. McCready is all over the place with a goofy side arm stroke and stance.
But both players reached the top of the world status in their respective generations. tHey both went about it in completely opposite fashions. What was the one thing they both have in common? Natural talent is my answer.
Here's another example of pool players. Me vs Corey Deuel. We both are from the same room in Philadelphia. He was 5 years before me in that room, but the same players were still there for both of us, save Caras. We were both around super high level players. We both had access and participated in the same weekly tournaments, gambled with the same old retired guys in the afternoons, gambled with the same guys in the evenings. I know he put in tons of time, but so did I. I went a period of at least 5 years when a teenager of playing probably an average of 5 hrs a day. I had the desire. I used to write lists of the people I wanted to kill on the pool table, and the order I was going to do it in. He not only got to the top of the local scene, he got to the top of the world. I can't even beat the mid level locals. What separates us? Natural talent is my answer.
Lets look at sports where there is total and rigid structure, unlike pool: Olympic gymnastics. Now, I'm not an expert by any means, and all I know about the Olympics is what I see on tv every 4 years.
But in that world, children from every country in the world that compete in the Olympics are plucked from their parents home every morning at like 4am to go to the gymnasium, then they go to school, then they go to the gymnasium again, then they go home back to parents for dinner, homework, and sleep. This continues from the time they are 5, till they are 15. These kids all have rigid and structured practice sessions, coaches, local, regional, and national competition. Yet, they don't all make it to the Olympics. Hell, even on the local level, there are probably kids that suck, and kids that are great. Probably only a tiny percentage make it to the national level, and then the Olympics. Why is that? They were all afforded ALL the oppurtunities mentioned in this thread with regard to becoming a world beater in pool. My opinion is some people just have it, and some don't. The "it" is talent.
Good discussion going here.