Gem from "The Closer"

I've long been a fan of Jerry Van Dyke's twisted phrasing as the "Luther" character from the television program "Coach." Luther would utter things like "It makes want to curl up into the feeble position!" (quotation may be imprecise, but you get the idea).

The other day while a DVD of "The Closer" was playing, a suspect in the interview room was relating something his girlfriend or relative kept telling him over and over. He said it was her "mantro." I found that a great touch to the dialog, taking it as a would-be accidental melding of "mantra" and "motto." I wonder if it was scripted or ad-libbed?