Pretty much this. If you don't understand the theory behind a thing, you don't understand the thing itself. I get contacted by a young photographer at least once a month asking to shoot with me second camera... and they are ALL missing the fundamentals. All of them shoot in automatic modes on their camera... they don't know how to control the equipment they are wanting to make their living with. They don't know how to capture good images, they've only learned how to push a button and let the machine make decisions for them. I end up telling them the same thing every time... if you aren't ready to learn yet you aren't ready to demand someone else pay you for it.