Or you know, maybe she always had this ability and never used it. To create a limb out of thin air to have it fall on the ground is pretty useless.
Unlike Skywalk, there isn't any moment before this arc where you think: "god, if only Robin could create limbs out of thin air".
yes and you got a point. either she learnt how to use his df better during time skip or we saw something not really new for the first time, it's still undeniable that oda changed something in his use of her abilities, i'm thinking about the clone thing when facing trebol at the underground port beside this one moment we are talking about. wether is good or bad i really don't have an opinion, i'm just guessing to figure out how it works, and it's working slightly differently from prets.