The Technique of Travel : Page 102
Fasten the ankle straps, or improvise some other means that will prevent the escape of the ski should the boot come out of the binding. A runaway ski is only a hazard to others on a practice slope. On a tour, miles from help, you may be seriously stranded if your ski escapes, to shatter against a rock, or if both skis schuss by themselves to the bottom of distant, separate canyons.
On long level or uphill stretches release the downhill tension of your bindings. If the toe irons have no touring hitch, it is sometimes helpful to run the cable direct from the forward attachment, inside the irons, and back to the heel. If tension is not released, an efficient stride is difficult to attain, while blisters are not.