Ambient Occlusion Setup time...

[Kruzschev]

Well a possible workaround for relative flat faces that it get's smoothed over several times over or with your 'Divide Rigidly' function applied on it so it should give a more smoother AO

through it wouldn't really work much seeming as this AO function calculates via geometry casted fake 'shadow's or so I guess, perhaps as well some light added on it might manipulate the AO behavior a bit but I dint tested it yet so far

In this case it seems to be more suitable for environment styled models or models with alot of small stuff added on it