Not in writing per se: Most editors catch the flaws of their authors. Hearing them speak can be something quiet different. Makes me wish that the old military adage that no soldier should be offered a microphone sometimes be applied to writers.
Not that we don’t all make a mistake here and there.
I’ll bet even William F. Buckley chose the wrong word at least once, especially during cocktail hour on his sailing of the Atlantic.
But one should, at the very least, know the rules of grammar and convey them through their speech and the written word as faithfully as possible.
Why? Because these are the only methods of handing down our language. Language will certainly continue to evolve along with humanity, just as it has since man spoke his first word, right through the time of Shakespeare and beyond.
It may not necessarily make us clearer, but it shows respect for the words which are, after all, a reflection of our heritage.