Thanks all for your answers! Maybe I will just write a book (or an ebook) instead of trying to sell individual tutorials. I am torn though because I always see crocheters selling patterns and I know that people buy them - and they sell them alongside the actual product they are teaching.
I am really just trying to diversify to increase my income by doing more of what I love; making jewelry, teaching others, and writing! The problem comes with the overlap - as long as I am still selling the jewelry it's sort of a conflict of interest to teach others how to make the same designs (at least for free). And it doesn't make sense to spend the time designing jewelry I don't plan to sell just for the tutorials.
Anyway, thanks again for your input. I have some more consternatin' to do :)