Rather than trying to predict if it's a good idea, or not, what would have to be true for it to work?

• FedEx would have to develop a proficiency in consumer marketing that I have not yet seen from them in the past.

• The founders and principals at ShopRunner would need to stay for a while. Historically that doesn't happen at big company acquisitions.

• Target or Walmart would have to adopt ShopRunner, which looks increasingly unlikely with Target's success and the launch of Walmart+.

• FedEx would need to acquire additional consumer assets. And probably a payments company.

• ShopRunner would need to grow. A lot.

The theory is this - by controlling the distribution channel - in particular the payment relationship, you can control which carrier gets the parcel.

In short, I don't think Amazon is losing a lot of sleep right now.