If your omission of what you
assume is "unimportant detail" leads to your audience misunderstanding the "important" detail, you actually are
failing to communicate.
It may also happen that the one person who you felt was not "worth the trouble" turns out to be someone who will be very important to you one day, like a potential business partner or investor, and who interprets your misuse of language as ignorance.
There's a difference between obsessing over unimportant detail and being thorough, IMHO.