So I've looked into this a bit, but I think an informal survey is in order. Can you breath out of both nostrils at the same time, or through one nostril that switches to the other after a few hours?
That's an interesting question, actually. My right nostril has a very low flow of air, whereas my left does the majority of the work (unintentionally). However, they both do work.
What you're referring to is a little known medical condition called Coke Nose, or "Coca Nosetra" in Latin. You start out the night being able to take in air through one nostril, then that one stops working for some reason and the other one opens up.
I'm breathing out of both nostrils at the moment, but sometimes that happens to me when I lay down to go to bed... whatever side I'm laying on will be the one that gets congested by something. If it starts bothering me then I'll flip over and lay on my other side and it slowly changes to the other side being congested. I never really knew (and still don't really know) what it is, but figured it isn't a big problem... I can't imagine having that regularly throughout the day though, that would annoy me to no end.
I have a slightly deviated septum, so more air goes in and out of one nostril than the other. But usually breathe through both.
^ I have a deviated septum, as well. I was just discussing this with the xcharged. The E.N.T. recommended breaking the darn thing but I didn't want to. It's not a medical condition. It's nature. You will ALWAYS have a dominant nostril whereas with your hands you will have a preference to write, eat, je... I mean, play sports with one or the other. Unless you're Lance Berkman, then you're good batting from both sides. Anyway, I digress... even if your nostrils are stuffed, one will always be breathing more than the other. These will alternate with temperature, pressure, snot, etc., Just like you have one dominant testicle and the other is there for backup [kinda like a hot swap hard drive on a server ].
Not anymore. My IgE is gone. No more Mast cells. I am prime for a helminth infection. Sorry, just finished my immunology block.