Some of you might or might know I was quite an accomplished musician earlier in life. If you watch my training videos there's usually some of my music over the top of the sound of weights clanging and grunts being grunted.
Now, some musicians play by ear. This means they don't really know the theory but they do know to play. Sometimes this might mean their repertoire is somewhat limited, but on the other hand some of the worlds most acclaimed musicians fit this category.
When I played, I had a reasonable knowledge of theory but got to the point where I could kind of ignore the theory and just play what I wanted to hear. My good friend and now online PT client Dean Gaudoin who's talent and knowledge of theory greatly surpasses my own would be able to hear what I was playing and tell me "oh you're playing the minor seven with the added fourth, so I'll play this to accompany it"... and I'd have to look at my fingers for a bit and then think "wow he's right, that IS what I'm playing".
Now then. For some reason I can remember many years ago reading an interview with guitarist Joe Satriani, and the interviewer raised something about a particular player "not using scales". In other words, playing by ear. And Joe explained "whether he realises it or not, what he is actually playing is the pentatonic blues scale".
So... just because you're not aware of the theory, it doesn't mean that what you're doing is not explained by theory.
Training... or more specifically, dieting for weight loss and body composition goals is very similar. If you are successful it is because you have hit suitable total calories, fibre and macro ratios. You might not be tracking your intake or setting targets, you may not agree with or believe in the "If It Fits Your Macros" concept, but that is still what you are doing. The only difference is in actually determining those nutritional targets and having a plan to ensure you hit them, rather than just happening to get it right by eating random amounts or random foods.
I see a lot of industry types and assorted know-it-alls scoffing at the concept of Flexible Dieting or IIFYM, interpreting it as "you're saying you can just eat as much as you want of whatever you like?" Clearly that's the opposite of what it really is. What it really means is having targets corresponding to your requirements for energy, protein, dietary fats, fibre and so on, and then choosing appropriate amounts of different foods to meet those requirements.