I couldn't agree more ALAN
I was very keen to point this out in the original post:
Using this knowledge of the “rules” one of my favourite “songwriting tricks” is to break the rules and use a "non-chord scale" chord
The bottom line is if it sounds how you want it go for it
Music theory will ALWAYS be able to explain the "why" something sounds like it does, whether it be an interesting "clash" or notes or something that sounds "right"
I love:
"the rules" are a useful slave but a terrible master.
My personal "mantra" regarding music theory, which I think fits with what ALAN is saying is:
"Music theory is the map, not the journey"
A knowledge of music theory WILL enable you to find quick ways to right songs, and contrary to popular belief a knowledge of music theory does NOT mean you can't come up with interesting songs
However, like a journey it can sometimes be beneficial to not follow the map and see where it takes you
You may find a "hidden" forest, a beautiful lake, some scenic views to make the journey more interesting
BUT - all of these things were still on the map and you can find them after your journey - if you knew what you were looking for you could have still found them on the map and got to them quicker
I think this analogy works really well for songwriting / music theory
The point is that it doesn't matter how you get there - as long as you get there!!!