How often does any checked bag stay outside on a baggage cart for long periods in the pouring rain with the zipper straight up? You have to give up something when you want lightweight and compact. Wrap delicate things in plastic and figure worse case some things get a little damp. So what, you don't need those dirty clothes any more, you generally use this duffel on your return leg home only.

Notice that bag is 14 inches in diamenter. Place human left hand palm on bag left end; place human right hand palm on bag right end; bring human hands toward each other with 0.5 foot pounds of torque in a smooth continuous motion until palms are almost touching. Congratulate self for another successful completion of duffel packing operation.