Ah, I just noticed you are the OP. Sure, you have to start somewhere with any analysis, and Poisson is the place to start. Anyone (like me) can then question

Ah, I just noticed you are the OP. Sure, you have to start somewhere with any analysis, and Poisson is the place to start. Anyone (like me) can then question independence assumptions from the sidelines. I was moved to speak up originally because a commenter referred to inspecting the logs to verify the Poisson assumption, and in my experience, looking at the data is always an excellent principle, and generally preferable to just stopping at an intuitive understanding of the arrivals process.