Interesting...  I actually teach a workshop here in Arizona from ages 10 and up, and with about 16 people.  What I've learned and its been quite interesting is that to me it seems the progression lies in 2 things... mentality and conditioning, with conditioning being the most important.  I have some students learning at a rapid rate, while others learn at a slower rate, or more conservative.

Take someone who lifts weights and is involved in a sport, vs. someone who casually exercises and has never done any sport.  Because of prior conditioning the person who is involved in sport seems to excel faster than the person that doesn't.   TRUE STORY: Just got a friend into Parkour/freerunning/tricking last week... first day in the gym he watched me do a back full. (backflip twist)and he wanted to learn how to do it, after he just barely learned how to do a backflip... I thought HAHA took me months to learn that... eh guess I'll show him how and watch him eat sh*t...... I failed to mention he just came off firefighting season and those guys train ALOT.  He sets.. goes up.. and almost hit it..I was in shock    after about 3 more tries he lands his first backfull.  Something that took me months to perfect took him minutes... I was pissed but happy lol, I'm sure some of you know the feeling. 

So overall I think conditioning, which is something you can work on can help you excel, but you must also learn to clear your mind which for alot of people is hard and thats something that I think starts out when your young.  Not sure if this helped or was good info for ya but take care and train safe. 

Interesting question.

I think it's the opposite, at least it seems to be in my personal experience.

With our group we are all pretty much beginners; Alex, Chad, and I pretty much started at the same time so it's an interesting comparison.

Chad was probably the best-conditioned of all of us when we started. He is a Crossfit Trainer and works at a gym. Alex and I, I dunno; I have my ballet background but I was getting older and I had a pretty long streak of inconsistent training the past season or two, so I lost a lot of strength.

Alex did some gymnastics as a kid, and soccer; but I don't know how long into his adulthood those things continued (he will have to answer that).

I have done ballet my whole life, and also dabbled in martial arts, yoga, other forms of dance, weightlifting, etc.

Being female, I lack a lot of upper-body strength compared to the guys. So that's another factor.

That said, Chad and Alex have totally lapped me in terms of skills. I think they both have more strength than I do, definitely. However for me the mental game is HUGE. I am a total chicken when it comes to parkour. The simplest vaults freak me out; I know I am strong enough to do them, but I just really "freeze up" when faced with a new obstacle. This has improved with practice and conditioning, but I feel it is still a big hindrance for me. Meanwhile, Chad and Alex just decide to do something, commit, and do it. I have a hard time committing.

It's been about 5-6 months for us. Alex seems to me to be the furthest along in terms of skill and also flow. He also, in my observation, has been the most consistent with conditioning and skills training. My trouble is that I am sporadic; I go gangbusters with the conditioning/training for several days/weeks, and then I totally slack. It's just my nature.

If I had to put it in terms of a skills list, I would say we have all acquired the following skills over the past 4-5 months:

Me: Simple two-handed vault and lazy vault over obstacles no higher than my waist; precisions at about 4-5 feet wide, no higher than maybe 6" to a foot; cat/saut de bras from running and standing (ground level), across distances of no greater than about 4-5 feet; tic tac to cat across 4-5 feet. Still unable to do pullup or climbup, still unable to do a saut de chat/monkey/kong. No fear of heights, though.

Alex: Can do all the same stuff as me, but at greater heights/distances (usually at least 50% more than I can do), plus he can saut de chat practically anything, he aces the climb-ups, pop vaults, wall climbs. He is also Captain Precision. He has a kong-to-precision that is really coming along as well.

Chad: About on the same level as Alex, although I would say that Alex has more "flow," whereas Chad seems to have the benefit of more strength/conditioning at his disposal; or perhaps simply more experience climbing around on stuff/apparatus.

Comparisons are odious; I don't wish to do a big compare-contrast of my fellow traceurs but these are my observations from our training sessions. As mentioned, Alex and Chad both have completely smoked me in terms of skills development in the same amount of training time. For me personally the biggest thing (besides the simple fact of less body strength) is mental, and in some ways, I think, having to "unlearn" a lot of ballet movement. Over 25 years of that kind of conditioning kind of makes it hard for anything else to stick really easily.

I don't know if I answered your question at all, but there you go.