Currently Being ModeratedFeb 13, 2013 2:00 AM (in response to OrangeMarlin)
I have Apple TV with HDMI to my TV which I get video and sound via the TV. I also have opical audio to the soundbar from Apple TV. I can use just HDMI for video and sound through tv, HDMI for video (turn tv sound to 0) and soundbar for audio via optical audio or even just audio from the soundbar with TV off (need tv on to navigate frst!!). Apple TV 2 with Samsung TV and soundbar all works great.
So short anser, yes your idea should work, just the apple TV won't know the HDMI is just video, you have to turn the TV sound off yourself.!