John Gruber seems not to be a gentleman after reading about his behaviour in the story of CommonMark’s name: https://blog.codinghorror.com/standard-markdown-is-now-commo...
Jeff Atwood instead is remarkably compliant. I personally would have been instisting on „Common Markdown“. Especially with the reasoning, with John Gruber just not-replying until publishing and then being a child and applying double standards, when he himself caused the need for CommonMark due to the inconsistent description of Markdown’s grammar.