What does this strap in the rear pocket of my Performance windbreaker does/for???

The coat stuffs into the pocket , and the strap goes arond you so you can cary it like a fanny pack

Or maybe it's a bike theft prevention system (while wearing parka, snap belt around bike frame, and carry bike behind you). (See, e.g., https://www.bikeforums.net/showpost.p...83&postcount=1)

Or a handy moose cage (just in case for those longer rides in the woods). (https://www.bikeforums.net/showthread...ighlight=moose)

When I can't make it to the top of a hill, I carry my bike strapped to my back!
Mud