Unless you are infirm and need the help of poles where its level, they will offer you nothing until the angle gets above maybe 30 degrees. So do you hike mountain sides? If not you may find that you end up carrying them on your pack because it takes less energy to carry them than to pick them up and swing them with extended arms. When its steep enough to lean into them and thereby add your strong chest muscles to those of your legs. It off loads your legs and knees but of course you need the arm muscles to make it work well, but you kinda become a bent over quadruped. You can consider carrying one hiking pole, it does similar things, is lighter, and consumes less energy in the flats.

As far as using a pole for a cane, I found when I broke my leg that you use the cane with and along side the good leg.
Jim