User blog comment:Fliu/Chapter 944: Big Mom Incoming/@comment-28995593-20190531121707/@comment-2600:1702:3C50:A6E0:4985:DF34:51D5:9204-20190602051823

True enough, the devil fruits can take some practice to utilize and how fast one learns depends on the person and the circumstances. Kaku while experiencing strange changes within his body did manage to adapt rather quickly. Luffy has also shown adaptability over the years due to needing to improve on what he already knows. Law and Sabo did have difficulty at the stages mentioned, although in their cases I would say that this is due to the fact that they had just gotten their powers and were still experimenting with them to learn how to use them properly. Same with Kaku. Brook had no reason to believe that there was more to his own power until the time-skip. As for Tashigi, her experience is understandable as she was in a body that was not her own utilizing powers that were not hers. Similar to Choppers body when his heart was switched.