Just thinkin'
How about using 6 Memory DC's at same time and have the zorder take care of the hiding for you using points globally and assigning needed one's to memdc's as warrented? Someday I'd like to try it when I'm really due for a huge headache but it seems to me this would work pretty simple (This is where someone has to copy, quote and bash me back into my senses so I don't try this)