That translated into martial arts is roughly the equivalent of a 4th DAN, but for that you need longer due to 'regulations regarding examinations', waiting periods between 2 examinations.
Depends on the martial art. The most modern practice recognizes natural talent while incorporating considerable traditional technique; I assure you, everyone does not walk into their first day of training on an equal basis -- I've been teaching for decades and I think I've seen about every level of beginner skill there is. Some people are simply gifted. Certainly from there on in we see the difference between the shows-up-once-a-week and the person who seems to be there every hour they can possibly manage.
Also, more on topic, I can definitely assure anyone who is curious that you're not doing high level thinking when executing advanced martial arts techniques.
All you really need to do to understand this is think about bike riding. When you learn, you learn, you think like crazy. Which does you very little good. But eventually, you internalize the process (that's what I call it, anyway) and you can do it while carrying on a conversation with someone else, paying almost no attention at all to the activity of riding the bike. Those near-instant balance corrections, the precise amount of handlebar control and lean for cornering, all of that comes from "underneath." Same thing for advanced MA.
That whole business about finding your calm center and holding it -- that's a real thing. If you start thinking under threat or pressure, your performance will drop like a stone. The best technique comes from a relaxed, centered condition, accepting of whatever comes.