The dimensions described are to the front center of the baffle. Sorry if that wasnt clear. I have already cheated your seating position back as much as I can while keeping a good listener to speaker ratio. If you move back further you may hear 2 speakers and not a transparent soundstage. If you treat the sidewalls you will definitely have to move forward. The apparent width of the soundstage will decrease dramatically, as you lose those strong lateral reflections.
I'm not sure about the space you are, or will be in, as you mentioned a couple, but you can reverse engineer my math and make it work for your next room. This only took me roughly a 1/2 hour, so no biggie. It was fun.
