In my times of serious track-bashing (have over the decades, mellowed / experienced some diminution of zeal and interest), I was rigorous about considering a line to count, only if I had done it in daylight, thus seeing something of the scenes through which I was travelling -- even underwent some heart-searching, concerning foggy conditions. This was re rail travel in Britain: anywhere abroad, I've "counted" all stretches covered, whether in daylight or dark -- it seems a bit crazy to get "precious" about seen-or-not-seen, when one has no prospect anyway of ever adding all the lines in a country to one's collection.
I had, way-back, a line-bashing contemporary who was notionally as hard-line as myself, about "daylight only"; but he was a bit inclined to cheat -- in the case of a line which he desired, and its traversing being difficult to repeat: though he'd travelled over it in the dark, he would sometimes "decree it daylight" concerning that particular bit of trackage.
Some while back, I started a thread in the Railway History And Nostalgia sub-forum, touching on this general theme -- "Line-bashers -- unintended unconsciousness, and addressing of same", first post 18/8/2017; thinking there, more about the issue of "can you count track which you travel over while you've unintentionally dropped off to sleep?" (as in posts #11 and #12 above) -- which with my now being an elderly gent, is nowadays for me a considerable bugbear to reckon with as regards travel over desired new track.