That is a nonsense phrase. 10 times fewer is a mathematical statement. 1x or one time is the whole quantity. 10x is ten times the quantity. 10 is ten times 1. Therefore 10 times less than one must be negative nine. How does that work? How do you have a negative number of ebola cases? Do the people who write these things even consider what they are writing? Or do they have the idea in mind and just write some words assuming the reader can guess the mind of the writer? Would the reader learn anything if he could read the mind of the writer?
I agree with your mathematical analysis. Perhaps the expression n*10^(-1) was lost on those folks.
The 'X times less' bit has been going on about a year now, when they could just express their intended reduction as a percentage of the previous number or a simple fraction of a previous value. With a mathematically dumbed-down population, who's to know, beside those of us who work with numbers every day?