To me its more like you should strike with the forefoot but with the foot almost flat (as opposed to running like on tiptoes) so it feels as if you are instantly rolling onto the mid part of the shoe. Or put slightly differently- the middle of the shoe is what catches the groud first as it moves backwards relative to your overall direction of travel. There was a whole huge thing about barefoot running but doing miles of it on grass really did help me retrain as a former heel striker.