I think theres truth to both approaches, in actual use.
I tend to air mine out quite often anyway.. because I want it to work the moment I put it on, not wait for it to fluff up! In the long term though, it'd be best to just leave it alone, or not compress it at all.
Interesting. Maybe I'm mistaken. Take what I said with pinch of salt about getting it out.
I need to check up again.