It isn't always easy when something does seem to be common knoweldge, but you are correct that people try to be more understanding. I have adopted the attitude from this XKCD comic. https://xkcd.com/1053/
Ironically that comic and XKCD in general falls into the category of things that are very widely-known but people still present as new information. (The prime example being cryptography discussions linking to correct horse battery staple.)