Here's a secret... I hate writing. But something in me needs to do it. Ya ever watch Dexter? Writing is my "dark passenger."
But you are astute in your observation of the necessity of writing to promote yourself. I started years ago with a crappy little newsletter that I published that I'd hand out to people at the crappy little gym I worked at. I typeset it by hand and photocopied it on my gym's xerox.
Then this world wide web thing started growing. Mel Siff had a wonderful online forum which I participated in, and that got my feet wet (and my ass handed to me... his forum was full of folks with more brains and experience than I had, and if you weren't prepared to fully support everything you stated, they were quick to educate you. Folks like Louie Simmons, Dr, Verkoshansky, Dr. Michael Yessis and a bunch of other folks with more titles and initials after their names than I'd ever had were regular contributors, not to mention Mel Siff himself, the reigning king of Physiology and Biomechanics at the time). Then other forums followed, and although the intellectual sparring wasn't near the level of Siff's forum, at least I could hone my skills and sharpen my ideas.
Eventually my own forum began, and my newsletters went digital. About 7 years ago I started collecting some of my writing together, improving on it and then putting it together in my first book. Since then there has been the blog world, and many websites have taken notice and asked me to write for them.
Now I blog weekly and am almost done with my second book, for the same reasons you find the need to write. It helps spread the gospel of your philosophy, and there might be some stuff that needs saying. My gym is built on a philosophy that was created, tested and shared from my writings. As my tribe grows, so does the need to keep the information flowing, but frankly, as mentioned earlier, I dislike the process. But the brain needs a vent, so I write.
My first breakthrough idea was when I asked myself and the universe why am I doing all of this? Why am I hoisting around heavy toys and straining myself to limits I didn't understand? Starting like most folks, it was to get bigger and look better, but after a couple of years of that, it seemed silly. What's the point? Any goal based on external feedback exclusively is shallow, or at least lacking in true empowerment.
That got the words flowing, figuring out what the purpose of strength and fitness truly was. I'm still figuring it out almost 13 years later.
I don't know if that helps at all, but that's the genesis of my writing. Being an avid reader helped too, and reader other iron heads who are superior writers... Dave Draper, Krista Scott Dixon, Dan John... always keeps the flame stoked.
chip