It keeps everyone off edge

Fareed Zakaria, in a Freakonomics podcast episode (#538 – “Are we living through the most revolutionary time in history?”), was describing how Iran attempts to subvert Saudi military strength by sponsoring extremist groups in the Middle East. He says “it keeps everyone off edge” (at the 44:56 mark). This is a mashup of “on edge” (feeling nervous) and “off balance” (unprepared or surprised). Both phrases seem to fit given the context. A big thank you to Doug Pietrucha for hearing this one and sending it in.