I think you are on the right track but may be over estimating the "average" internet user capabilities?

I had to migrate a couple of projects from awful, big ridden, wysiwyg editors to markdown and it's a huge challenge. Many people expect everything to work just as Ms Office/word does. Anything behaving in any way different than their benchmark is wrong..

Now, going from such a mindset to Markdown is a huge endeavour. You need to re-educate your user. Many will never appreciate the raw, code-like nature of markdown and will dread it the entire time they have to endure it.