I think this is a gray area. The great (and sometimes frustrating) thing about pool is there are more different levels of defined ability (whether it is league play, tournaments, rankings, or other categories) vs other games and sports. Also, to prove this would also be difficult as you would need an appropriate sample size (just like proving any hypothesis), as well as all the variables and results required for the hypothesis to be proven defined ahead of time. That in itself would be difficult as everybody has their own definitions of this.
I would like to see a thread where 5-10 people are taken under a pros wing for one full year to test this. The pro would be living in the area of the students and the results would be documented via video/drill tests etc. The pro would have to be compensated for a full year of course monetary wise and the students would need 24/7 access to a pool table.
My guess is all the students would improve to various degrees, but the likeliness of one of them hitting a huge speed (would have to be defined as what actually "huge" speed means) in a year (with the assumption they are all beginners), is very low...but it would still be interesting to watch the progress and reports.
CJ once mentioned he could do what you are also saying JB, but he never followed through after many people told him they would volunteer for this test (myself included)...I live in Iowa though and he probably wanted a student in Texas....still, I would absolutely love to see this put to the test. Now 10 students is obviously lol sample size, but the documentation would be a great thread for pool in general (assuming all mud slinging would not happen). I also just think that some people have the natural ability and hard work to be able to get to the top defined level, and that very very few raw players can get to that top speed...doesn't mean they can't get good...but world class good is tough.