Most GA fuel injected engines are still started this way (at least the ones that I've flown). Prime it a bit, start with the mixture pulled back and push this forward as soon as the engine fires. Fuel flow as delivered by an injection system is set for idle air flow through the engine, or above. The mass of air being pulled through the engine at starting is not enough and would therefore cause it to be flooded. So the priming system overprimes the engine and by keeping the mixture in idle cut-off, you allow the mixture in the cylinders to weaken as the priming fuel is diluted with air. Once it reaches a proper fuel/air ratio, it will fire.