In addition, another benefit of running with a forefoot strike is to keep momentum while leaning forward and avoid jarring pressure going up your leg on each strike as you run. For example, if I try to land on my heel when running barefoot it physically does not feel right and when I do it the collision hurts. But walking barefoot and landing on the heel feels completely natural and pain-free - the step is very light and the contact point is maybe slight-heel-bias-to-midfoot, nothing like slamming a heel into the ground while running. When walking you do not create as much pressure through your heel unless you really stomp down on it for some reason.
We have some research showing potential benefits of running on your forefoot - does any such research exist for walking as well?