No, it means that you can leverage a more efficient part of an engine’s torque curve by supplementing with electric power at the low and high end (since motors have a flatter torque curve).
Basically with that cycle they can get massive compression ratios. As an example newer Toyotas are at 14:1 ratio with 41% thermal efficiency. That’s close to diesel territory on a gasoline car.
Naturally when you floor it it goes to Otto cycle and efficiency drops.
Also: start-stop-automatic for free ... I am still somewhat spooked when the motor just turns off going 70 km/h because the ECU decides that the ICE is not needed anymore.