youre a funny farmer dood.
good post.
well, heres my take on it, and, hopefully, if i miss something, other farmers will correct us both but..
if youre getting better air flow with the door open, it stands to seem like the same benefits would occur if you 'vent the box' if you will.
before i go further i need to ask what fan or air movement system you got set up?
do you have fans IN the duct?
one inline fan blowing into the box and the box disperses to the rooms?