Photomontage has come a long way from the days when a collage artist spent hours rummaging through a pile of magazines snipping out photos and sticking them down with scissors and paste. It's an ambiguous experience whatever you think. And some collage works best simply because the joins are bizarre .
Montage is a bit like graffiti but it had to wait until the invention of photography.
Or maybe the steam engine. Looking out of the window of a train human beings were, for the first time, exposed to a variety of places and scenes they'd only heard about or seen pictures of flashing by at speed. They may have been there in their dreams before but this was real. One minute a field of cows, then a mountain, a lake, a forest, someone shaking a rug in their backyard would unspool before the train traveller's gaze through the 'screen' of the carriage window, like scenes from a movie not yet invented. Then came the real movies, with the narrative ready-made for the viewer.