Even the best writers can attest to the benefits of having an experienced and impartial reader check their work for clarity, grammar and readability. As managing editor of Rising Up! / Viser haut !, a weekly blog published on the Christ Church Cathedral Major Fundraising Campaign website from September 2017 to May 2018, I was privileged to edit texts by new and experienced contributors. I have also edited magazine articles, reports and briefs, correspondence and manuscripts.
Your spoken French may be quite good and you may have the presence of mind to use spell check, but for the person receiving your message, a few simple edits can mean the difference between awkwardness and ease of reading.