To write or say something particularly tasteless, offensive or out-of-touch without even realizing it. Originates from Deadspin
's coverage of sports columnist Mark Whicker's piece about the wacky things that happened in the sports world while recently-found kidnapping victim Jaycee Dugard spent 18 years living in a shed.
Whicker signed off the piece with two of the worst sentences ever written: "Congratulations, Jaycee. You left the yard."