Your mistake is to project your own expectations onto others. No two drummers will start with the same strengths and weaknesses, progress at exactly the same rate, or have the same motivation to develop the same skills. It's pointless to measure the rate of development in years. Portnoy has distinctive chops which he executes in a very 'idiosynchratic' way; someone with abundant natural talent for rhythm may play for five years and gain highly developed chops, but may not be able to reproduce Portnoy parts, at least not without due attention.
AS for natural gifts, you seem to think that having to work on a skill means you never had a gift for it in the first place. The only reason we view certain players as 'naturally talented', Colaiuta, Weckl, Williams etc., is that these guys took their natural gift and worked and nutured them to their fullest. They were driven to woodshed the hardest.
I agree with part of what rolo said... being that skill is a much better word than talent .I dont recognize talent , its skill that i like to see.
Now as for portnoy.. pseudo-idiosyncratic better describes his use of chops. He has them for sure , but lets face it he idolized a drummer that wasnt that great ( you might know of him from rush) and thusly became a not so great ,boring and flashy drummer.
My comment about educating yourself in theory is still inteded for the same people i said before.
If i couldnt read music , count time , learn songs , and had no chops... Lets be real .. not many people would call me a drummer. Get serious , learn your craft.