Interesting. I was actually wondering whether alternance had its own philosophy, like Alternism. Maybe a French philosophy, as the terms are French. Did you synthesize it yourself?
I guess you could squeeze alternance into Utilitarianism by defining happiness as a state of dynamic equilibrium (I'm totally envisioning a chemical equation with that

), or of harmony with maximum displacement/ movement.
I don't know Jeremy Bentham, but from the bit I read of him 2 minutes ago, he seems to have an equation for calculating the consequences in terms of happiness of a certain action. However, he associated happiness with pleasure and absence of pain. This opens up some thoughts on this "happiness" (yeah, same issues as before). Part of that cycle is pain, no? You alternate between pain and pleasure, good times and bad, along with exhertion and rest. So Alternism (yeah, it's a philosophy now) would say an absolute absence of pain or a life of perpetual pleasure is not happiness at all. That's too far out, the Utilitarians would ban thee forever.
Now back to alternance and happiness: what about a dynamic balance between two opposites that are both what I would consider negative/ unhappy. War is the ultimate cycle of movement and stillness: intense combat broken by long periods of boredom. They say that war brings out the best and worst in man. Men trying to deal with life after war say they were so intensely alive in war, and can't deal with the stillness and triviality of ordinary life. Nevertheless, they are not what I would consider healthy or happy. What say you?
My first reaction:

Teeee heeee
My second reaction: Ash? Dude, I'm high on crack! *wipes nose* Ugh, is it still there?!
Note: I am not and have never been a crack addict. I get high on life. Thank you.