Being honest, I had to read this a couple of times, but when the penny dropped it made me laugh out loud.
A Letter to the Financial Times
Michael Skapinker refers to the use of double negatives. I am reminded of the linguistics professor addressing his class who said: "A double negative will convey a positive; a negative and a positive in conjunction will convey a negative; but two positives in conjunction will never convey a negative." Whereupon a voice from the back of the room piped up: "Yeah right."