Greg is the owner, founder, and primary author of the Frequent Miler. He earns millions of points and miles each year, mostly without flying, and dedicates this blog to teaching others how to do the same.
UPDATE 9/23/19: I've confirmed that points from Double Cash are transferable to airlines when paired with Premier or Prestige!
UPDATE 9/22/19: 1 to 1 transfers...
Since this post was first published, Amex has ended this exception for Centurion Lounges. The layover exception remains in effect, though, for Escape Lounges...