Right from when luffy discovered the gear system, we saw that he had complications using them at first, looking back when he fought CP to rescue Robin, first was the exhaustion with the gear 2 and then the shrinking with gear 3.
After the time skip seems he got better handling of them, now he is facing the complications from gear 4 be it bound man or tank man, they seem to have same disadvantage after using gear 4.
From look of things, awakening probably going to change a lot of things just like we saw on Kataruki aka dogtooth.
The suspense is killing xD
