I'm not even sure thinking too much about plot is a good idea. The "porn movie with a plot"-films I have seen were, although explorative and interesting, not very good at provoking a boner (or anything except curiosity, really). It's a good start. What I'm suggesting here is (at least in the form of execution) completely unexplored territory, the rules that we know from other genres may not apply in the same sense. We just have to explore to find out.

I don't think porn necessarily has to be low-brow. Exploitation films and other really violent stuff was pretty lowbrow at some point, but today the best films of these genres are as good art as anything. I'm not sure this analogy holds all the way, but at least it's a good argument that these things are worth exploring. It's surprising how culture and people can change.

I love to discuss this stuff with you guys. It's not really something you can talk about over dinner, or in any other 99% of social situations.

[Note that I'm using a liberal definition of art here - I prefer to use the word in its original sense, as "something really good" which provokes emotions, thoughts and daydreams.]