I finally made the plunge and contributed an answer to Blender's StackExchange.  It easier (and less scary) than I thought!

I have frequently heard, 'If you really want to understand something well, try to teach it."  My dilemma, and this is probably true of most enthusiasts, is that I never get to the point that I feel proficient.  This is particularly true with Blender, where you could spend a lifetime specializing in any one of several aspects (modeling, animation, sculpting, etc.).  The questions became, "How proficient do I need to be before I can teach someone else?"  Just as everyone has something new they can learn, I believe everyone has something they can teach.  

 So, as part of pushing myself to become a better artist, I decided to contribute to Blender's StackExchange (Heavens knows I look up enough answers there).   To be honest, I have made this decision a few times before.  Each time, I chickened out.  I wasn't ready, I didn't have time, The process was too difficult, but mostly just fear of the unknown kept me from following through.  This time, however, I actually did it and it's been a great experience!  Sign-up was easy.  Once I had an account, I could look through the questions and find something I felt comfortable answering.  I usually learn something with each answer, especially when I post an answer and someone else proposes what I consider to be a better way of doing things.  

I have nothing bad to say about the entire process except I wish I had started years ago.  I wholeheartedly recommend everyone involved in an open-source community contribute in any way they can.