Killer players come in all shapes and sizes, and from different backgrounds. Somebody who is musically illiterate and plays music by "feel" has overcome many obstacles to their musicianship, learned by trial and error, and has thus learned to fine-tune and trust their intuition. (This case can also exist for literate/trained musicians, the two are not mutually exclusive.) Trained musicians have been trained to quantify, so they can hear/play music, point, and say, "This is what's going on."
The very first thing I wrote, when I was seventeen (maybe sixteen) years old, was a little number I came up with on a twelve-string acoustic guitar. It came to me the moment I sat down with the instrument, I really liked it, and I wanted to expand upon it, but I had a really difficult time overcoming my writer's block. It sat on the backburner after a few failed attempts to tack some more material onto it. I tried notating it a few times, but was lost as to what I was even playing. About six years later, I had enough knowledge and musicianship to figure it out, and wrote down what I had on staff paper. Four bars of 11/8, followed by a bar of 5/16, a bar of 9/8, a bar of 12/8, a bar of 15/8, two bars of 12/8, another four bars of 12/8 in the next phrase, a bar of 5/16, a bar of 18/8, basically a meter change every bar or so, most of the chords were minor triads, but included such monstrosities as D11/F#, and Em(add#11,♭9), as well as secondary functions and some chromatic mediant relationships... No wonder I had trouble trying to describe this thing! Keep in mind that I started playing music when I was 16, and I was an ignoramus, so all of this technical jargon has nothing to do with being trained or untrained. It's really not all that crazy of a piece, though. The form is binary, for example, and aside from some secondary functions and odd tonal relationships, the A section stays in E minor and the B section is in B minor - classic key relationships (tonic and dominant). I'm proud to have made such a basic modulation using such inventive harmony. Anyway, once I had it quantified, I could see what was going on and started writing more. It all felt very logical once I could see the whole picture. I took my intuition as far as it would take me, and then used my newfound tools to complete the job.
Some people get bent out of shape over having to learn something new.
Some people put the time in, understand the benefits of their efforts, and are awesome to be around.