I think that, whatever your knowledge based around composition, you'll still just be composing what "sounds good" to you. The trick comes in with being creative and original. Anyone can do D# - D - C ...but no it sounds good and applicable so why don't everyone just use it?...sigh...
You're not necessarily limited to just the use of 12 notes over and over again...it's the creative use and combination and notation that makes it twinkly, pretty, silly, funny, sad, mad...or bad.
I try to be creative but I know I just do what sounds nice to me LOL