Board Thread:Theories and Speculation/@comment-33959444-20180610211826/@comment-33959444-20180613205626

Thekillman Actually, right after Kakashi transported the Shadow Clone, there's a panel showing the Rasengan "dissipating." After that, it poofs into a cloud as if a Shadow Clone being undone. Obito clearly noted the Kamui and thought the Kamui hadn't succeeded, hence why he said, "Looks like you were too fast with that stake, Kakashi. You weren't able to make the Rasengan vanish. You used your Kamui in vain." If Obito saw the Kamui on the Rasengan, he should have been able to see the Kamui on the Shadow Clone.

Obito's right eye doesn't have any feats of using Kamui on small objects. The only time I remember him using Kamui on a small object was the nunchuks which he transported from Guy. He was able to Kamui them and head towards KCM Naruto before he was ablet o hit him with a Rasengan. If that Kamui was so fast, I don't see why he couldn't Kamui a nail as fast as or even faster than Kakashi.