I was talking to a mate about this the other day.

He's just bought a Celica GT-Four and wanted to run it on supermarket fuel which I advised him not to. His argument (second hand via an ex Bentley tech, now multi-millionaire in-law) as that modern ECUs would detect the onset of DET via the knock sensor and adjust the timing/boost to compensate thus not melting the engine....

While this is probably true I don't think I'd want to risk it.