What is "fumblerules"

A fumblerule is a rule of language or linguistic style, humorously written in such a way that it breaks this rule. Fumblerules are a form of self-reference.

The science editor George L. Trigg published a list of such rules in 1979. The term fumblerules was coined in a list of such rules compiled by William Safire on Sunday, 4 November 1979, in his column "On Language" in the New York Times. Safire later authored a book titled Fumblerules: A Lighthearted Guide to Grammar and Good Usage, which was reprinted in 2005 as How Not to Write: The Essential Misrules of Grammar.