I was trying out one of those grammar checking programs the other day. It came upon the expression "not at all" in my document and issued the following advice: "not at all" -- Wordy expression. Consider "not" or "by no means" instead. I chose to ignore this sage counsel, especially the second part. Then, later in the document, the program said: "by no means" -- wordy expression. Consider "not" or "not at all" instead.
(From the "Rest" of RHF)