I feel this'd be useful to a film historian.
The analogical way I could put this is, in music; "underground" artists will have certain elements in their songs that don't work as a whole, but get cherry-picked by pop artists and implemented into a more widely consumable product.
Could anyone tell me certain things we see in modern films today that were originally only found in indie/art-house titles?
Examples of things could be (not saying these started as indie): the 360-shot, short burst grunge editing, having a one word title and the film shows a slate of the dictionary entry of that word, etc.
Thanks.