Hello shumway76 no one seems to have responded to your question. I was leaving it in the hope that someone with greater engineering knowledge than me would answer your question.
With injected systems it is very easy to flood. The primer pump applied for just a few seconds provides sufficient fuel for the engine to fire. When the engine is turned over to start it will also draw in further fuel if the mixture is not in the off position and therefore flood the engine. You will know that once the engine fires and runs it is important to immediately move the mixture to rich to provide fuel for the engine to continue to run.