Nissan did make a production rotary motor. It was only found in the first few production cars and quickly pulled. Please reread my first post. I mentioned it there. The S110 (1979-1983 Datsun 200SX)
That technology of dual spark plug was first found in Chrysler Hemi motors to try to completely burn the intake mixture before the exhaust stroke because it was being scavenged on the exhaust stroke. Porsche did not use that technology in their race cars till the near mid 70s. They had similar technology in one of their production cars by the mid 60s. One would think that dual plugging would completely burn the intake mixture, thus coming closer to the stoichiometric ratio and thus, having a hotter combustion and potentially detonation. Cure for detonation?? I don’t think so. Cure for complete combustion due to scavenging exhaust system. Yes.