Stonecipher admits that the MDC-led team's near tail-less aircraft design and complex engine installations were a calculated gamble. The concept included a lift-plus-lift/cruise STOVL configuration. As designed, a forward gas-turbine engine, mounted behind the cockpit, offers vertical lift, while the main power plant provides rear lift and conventional forward thrust. He feels MDC lost because the propulsion concept was considered "higher risk".
He was more or less right, although the source selection authority was probably wrong about LPLC and there were other undesirable aspects to the MDC proposal. But that doesn't mean that there was a requirement that JSF be single-engine. "Words have meanings", as someone said a few posts ago, and in the context of acquisition, a "requirement" has a specific meaning.