lol... well this is kind of a theater type room.... see the two speakers in the top corners of the rear wall? heehee... and it's about acoustics.
I wonder if covering that entire back wall would do anything... somewhat trap the reflections, so to speak. We hung curtains up around that kitchen area (there are hooks on the inside edge that you can't see) and it helped quite a bit... it didn't take all the echo out, but you could at least carry on a conversation better. That's a pretty small area where the curtains were hanging that made a noticeable difference. I guess that's why we were thinking the area below the chair rail might help.
Thanks for that link Fincave... I looked at it briefly and will check it out more. I'll probably give it to a few others and have them read up on it too.