I've been in the local running scene for time now. I have had success. I have had adequate failure as well. I do not do running for no reasons, and apply a lot of method to most of what I do when involved in distance running. the verdict is clear that midfoot is the more economy than heel/forefoot strike, which make for slower time and for increased mileage. you can cut the mileage in half chop with simple trick of just landing more midfoot on your runs. try it for 50 feet, try it for 100 feet. you will notice a difference. I have done it on the boat, even as the boat was departing from the habour. your foot naturally springs off the ground when you land midfoot.