Last week, Hudson’s Bay Co, the owner of Saks Fifth Avenue, announced that it is spinning off the luxury department store’s e-commerce arm into a separate business called Saks. Private equity company Insight Partners has invested US$500 million in return for a minority stake that values the new company at $2 billion. In an age where most retailers are still focused on breaking down barriers between sales channels, this appears to be a disaster in the making.  Why establish a standalone busi