While you are technically correct, that's pedantic and doesn't impact the conclusions of this article one bit, nor does it really add to the discussion. It's wr

While you are technically correct, that's pedantic and doesn't impact the conclusions of this article one bit, nor does it really add to the discussion. It's written for the layman, and chose to purposefully ignore technical details such as lim x->0+ 1/x = +inf and lim x->0- 1/x = -inf.