While I was rearranging my speakers the other day, it got me thinking where to place speakers that are "marked" LEFT and RIGHT. My Infinity's and Bose' both are marked L & R on the rear, but how to determine? Do you determine LEFT & RIGHT when you are in front of the speakers/HT watching a movie? Or the LEFT & RIGHT sides if you're standing behind the speakers. I tried both setups but found no discrepancies. What does everybody use as rule of thumb?