Well first of all, I'm not sure how we got on KO coverage, since that was very good this year. But with a punter like Foltz, 45th in net punting and 104th in punt return defense is atrocious. So if that means having Foltz kick differently to account for the deficiencies on the coverage team (in your eyes), then so be it. Since that is Read's entire job on the staff, I would expect him to be creative enough to come up with a plan.
But net punting includes however many yards the opposing team had on the return.
What's better? A team punts from the 10 to the 50. The returner gains 10 yards to the 40? Or a team punts from the 10 to the 40, the returner gets 1 yard to the 39? In the first scenario, the return defense looks poor. In the 2nd scenario, it looks great. Hence why net punting is the stat to go by.