Talk:Monkey D. Luffy Gum-Gum Elephant Gun/@comment-93.213.208.2-20170301135013/@comment-29682895-20170301135540

It can be, but skill books normally are a CHANCE on increasing a skill's level. With these super-evolved characters (like this Luffy), they changed that chance to be a guarenteed skill level up once every x amount of skill books. We don't know that rate yet, but it's working as intended. You'll level the skill up after you feed some more manuals.