There's no reason it shouldn't be fine with a guitar which hadn't bellied up. In fact with mine, after the strings had been removed and teh guitar rested it reverted to being level. The tension post should stop it bellying up again - it's installed in some guitars when they are constructed to avoid that happening, and to augment the sound.

As mandotim said, it can be reversed without any problem, if the changed sound doesn't suit you.