I can certainly tell whether or not the seat is reclined, but there is no perceptible difference in comfort: both modes are equally uncomfortable. I would guess

I can certainly tell whether or not the seat is reclined, but there is no perceptible difference in comfort: both modes are equally uncomfortable. I would guess that the previous poster meant something very similar, rather than hypothesizing some bizarre proprioceptive malfunction which left them unable to sense their body's angle of alignment to the floor, as you seem to have done.