User blog comment:Lasaro Ginjou/Gears to come.../@comment-4503935-20161014030635/@comment-5536072-20161016224524

Actually, gear 4th is not gear 2nd + gear 3rd. We have yet to see him combine properties of two gears in one. Basically: My point is, every gear so far has a unique aspect and focus. One more gear with a unique aspect is left, gear 5th (which it will be size, in my opinion) and then Gear 6th or Reverse Gear will use all of them in one. And then the Awakening I hope.
 * Gear 2nd: Blood, speed
 * Gear 3rd: Bones (Hone), brute strength. Slow but strong.
 * Gear 4th: Muscles (Kin'niku), explosive strength. Fast and strong.