I recall metal musicians I grew up with doing a lot of power chords and appregrios.
Can't finger like that on my beat up sixties guiar. I like to dig into the strings and if I ever consider being a performing musician, I can fly on these modern guitars from building up limber in my fingers, cause' I'm not too coordinated otherwise.
But I notice that a lot of these weird, classic rock songs have a lot of diads and triads, fretted slightly off the major scale.
I used to like transposing metal songs to my synth and making songs based on that. Kind of made it dark and gothy. Almost strangely harmonious.
I did an old gospel folk inspired recording that I came up with from practicing Pink Floyd's Hey You (off their album The Wall).
I don't have a 12 string and had to open tune to get the sound that more closely approximated what I was looking for.
Not for a professional setting, but I have come up with a lot of weird sounding chords that way.

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