Who put that on their packaging?
Anyways, dual channel is real finnicky. If someone put that label on their memory packaging is <might> be because the two modules had slightly different timings. Or one might have had a different number of chips than the other- another thing that can screw up dual channel.
Duel! Dual! Duo! doh!
It was Kingston!http://www.newegg.com/Product/Product.asp?Item=N82E16820141470
Check out the picture, it says "Not Dual Channel compatible"
That's true about what you say above, but its a single module... I'm not sure why they have that sticker there - perhaps it was a warning that it might
But my pessimistic side would believe otherwise.