Although "rule of thumb" is commonly supposed by feminists to indicate male brutality using a stick no thicker than a thumb to beat the wife, there is evidence that the term was initially in use by builders, and its current use approximates to the original.
http://www.phrases.org.uk/meanings/rule-of-thumb.html
I agree with the author that the idiomata are overused, mostly by the unimaginative writers, but she might have looked a little further into the origin of terms in order to enlighten her readers, more constructive than merely railing against them.