Aargh, trying to find a blog post from 10β20 years ago where the title goes something like "You can never tell anyone anything" or "People can't be told anything" about how difficult it is to communicate truly new ideas to people unless they've encountered the same issues you have and already sort of agree with you and you're just providing the last piece of the puzzle.
Could be Joel Spolsky, could be someone compleletely different.
Could be @Jeff Atwood ?