If the number of people in the system remains constant over time, then you can measure throughput by counting the rate at which people either arrive or get proc

If the number of people in the system remains constant over time, then you can measure throughput by counting the rate at which people either arrive or get processed. And you're right about throughput, I was implicitly holding the number of people in the queue constant, and you can obviously add arbitrary delays and increase the number of people in queue without touching throughput.