@skua @epiceneVivant yeah, it is almost like he can't see through the tube that we see as clear, as well as we can. He has to go right and check twice to see if he accomplished the task, walking straight by the visual indicator that is clearly showing that no, he hasn't.
Wild animals don't waste energy, their lives are too stressed. If he could see it he wouldn't check until done.
The tool use is the main thing, but there is a 2nd paper in this if it could be confirmed.