This is a useful definition of a system because it does exist "everywhere one looks for them". If you're unable to look for anything new I would venture to guess you'll find nothing new.
After playing a lot of my best matches subconsciously (in The Zone) it is challenging to explain some of the shots I was able to pull off. I can't even try to explain some of the phenomenal things I've seen (from many players) in the midst of a 20 hour session, they seem "supernatural".
If someone's really struggling to improve and they don't believe in developing a better system, then they may unconsciously not want to improve. The mind can pretty much achieve what you can conceive so make sure you at least "think" you're improving every day. Sometimes we just have to "fake it, til we make it," and see ourselves as a better player, in a better job, or in a better relationship before it actually happens.
I recommend the book 'Zen in the Art of Archery' to anyone wanting to learn more about learning to "play in the zone," (it's the first book I read on the subject and it's superb). imo