This is one time I'll give Cook a hand-clap but it depends if my theory is correct. Which is, the sales have plateaued at a really awkward time ie 12-18 months before the 10th anniversary iPhone. Usually, the outer design is used on the tick-tock two year cycle. However, the tock on this cycle clashes with the aforementioned 10AiP. Sooo - does Apple minimally change the outer design in order to provide room for a price-cut in this generation? There will be enough technical wizardry to justify an upgrade. Better camera, A10 chip, potentially faster RAM and bumped base flash amount. Further, we don't know what screen technology may come, we don't know what additional tech they've added to Lightning. In addition, my best is there will be some sort of integrated circuitry for wireless charging; not necessarily for the phone but perhaps for AirPods.
And don't forget that design also goes more than skin deep. We know Apple has cracked terraced battery tech so perhaps there is room for super-fast charging or more battery life.
This could be a really smart update and compelling enough for current 6/6+ users coming to the end of a double year service plan.
