Are you also familiar with extension tubes? I think in both the reversed lens and extension tube the lens sits further from the film or sensor (focal plane). So

Are you also familiar with extension tubes? I think in both the reversed lens and extension tube the lens sits further from the film or sensor (focal plane). Somewhat counter-intuitively, at least for me, is when the lens is focused at infinity, it's at its closest point to the focal plane. Moving it further from the focal plane focuses closer.