I was a terrible heel striker with low cadence. I owe Altras Escalante + hill sprints a big improvement in my running form, i.e. I passed to midfoot contact and cadence is about 180+ even on regular runs.
They are comfortable and good for fastish ride when I'm ok to press. Don't like them though for recovery nor for long runs. They are complete disaster downhill.
It might be an overkill but I rotate few pairs of shoes with various drop/weight/cushion depending on workout and my mood. For slowish stuff I prefer Cloudflys which are quite heavy 6mm but a lot of cushion; for a simple run I use Escalante or Nike Elite 10mm; for tempo or long repeats I use Nike Elite or Flys or Bostons 8mm; for track I often use Streak LT 4mm.
As quite a few people mentioned in this thread doctors recommend to rotate shoes as each has its flaw and when you run in different shoes you avoid a constant stress on one zone.
IMHO you should keep 4% for the race and big workouts; use slower stuff for regular training. It's like bike training on heavy duty wheels and using carbon feather wheels for the race.
PS. I'm a hobby jogger with 1:19 HM PB at late 20s.