I see the distinction you're making (I think), but I still don't see how that invalidates GP's analogy. Surely "running" a wavefunction is computationally cheaper than re-evaluating the particle's characteristics at every universal frame. Perhaps it's not so much about our own "watching" but rather "do not calculate when irrelevant". My own analogy might be an online map frame like google maps, where tiles outside the viewing box are not loaded. This is because we can tell what needs to be calculated by the bounding box of the viewer without needing all the other finer details. I see it more as a lazy eval.