Board Thread:Theories and Speculation/@comment-40250240-20190723070503/@comment-25122992-20190723100421

Copying isn't only about memorising a jutsu in action. I mean, jutsu are usually performed in a quick succession, while it's Sharingan's heightened perception which allows the user to keep up with this performance. Moreover, thanks to this very perception, the Sharingan wielder grasps all the details up to the smallest ones and can analyze them to use the jutsu themselves as a result (if they're physically capable of performing it, of course). Hoki's photographis memory is surely helpful, but he's neither able to keep up with jutsus' speed nor break them down for analysis by noticing the details.