I would propose a potential user as someone interested in some of the meta considerations and patterns of statistical reasoning, aka machine learning. There are is a vast amount of particulars the second hand on my watch operates (e.g. vibrating quartz, digital), but I can use that mostly reliable device to investigate higher level phenomenom, like calculating distance of planets by timing their movement. This library opens a direct line to these algorithims such that one might intuit, and apply, their high level behavior; as I could not time planets if consumed with the fidelitity and reliability of resonating quartz, it would slow my ability to explore this kind of reasoning if concerned with the minutiae.

That said, all points taken. If this sparks interest in someone, as is stands, it would be on them to dig in to all the considerations you've outline.