No test required. Your image illustrates the split.
Black and White conversions sometimes,simply, highlight the fact.
I don't have enough experience to say whether the issue is random and will appear every now and again
or if it will always be present.
Earlier Leaf backs were very prone to this problem but were not alone.
I've seen it with various Phase and Hasselblad backs and more recently with
the Leica M8,M9 ,and the S2.
As far as I know,the remedy is a manufacturer re-calibration of the sensor
Track down Yair Shahar ( Yaya ) on this forum,now with PhaseOne, who could
very capably infirm you on this topic.