Hana Hana no Mi is eaten by Nico Robin, as we know that she can grow parts of her body. She usually grow her hands to attack, or to defend her. She also can swing or lift her or other people with her growing hands. She can easily break the bones of her opponents, just like when she used clutch or twist.
I know that if her body parts are hurts, she also feels the pain. But is that mean when she used clutch or twist, she used her "normal" human strength? Because she doesn't seems no trouble when do that to her opponents. Or it's because the Hana Hana no Mi that also give her superhuman strength?