Let's look at what it takes to measure and analyze margin accurately in a world where formerly disparate channels are quickly converging. On the consumer's omni-channel path to purchase, there are many widespread retail practices that act to distort the true picture of margin.Double CountingIn omni-channel sales, many retailers have not yet sorted out which channel gets credit for the sale. Let's say the customer ordered on the web and picked up in the store. Whose sale is it?