Maybe you could post a picture of your HT room on how those IBs are visually. I too am thinking on a similar IB config since the main room will be the living room and I have a good size attic space above the living room. Matter of fact, both of my IBs would be sitting on part of the load bearing walls. It would seem that in theory having them split in the middle on the sides would work just as well as having them just up front.
The forum's software doesn't allow picking out individual posts from a thread to create new thread.
So Instead of continuing to add on to a thread from 2006 let's start a new thread dealing with the specifics of your room or one that's a generic thread dealing with rear mounted IB's.
Also people need to understand that the FAQ's are not something etched in stone having been passed down from on high. They are conservative recommendations/guidelines that error on the side of making sure even the greenest nOOb doesn't make a big investment in time/money then be disappointed in the results.