In this article, Ghislain mentioned Yuzu a few times.
"Jumping is great, you need to jump, but you need everything. If you don’t have good spins and you miss a jump, you have nothing to hold on. When I worked with Yuzuru Hanyu, Hanyu was good in everything. He had great spins, great skating skills, great turns, great footwork, great jumps. Beautiful skater, beautiful body! So if you have all this, the package, you can afford to miss something and still be great. But if you don’t have everything, and you miss something, you’re stuck."
"When I worked with Yuzuru, the problem with his ankle really diminished a lot of stuff. Before the Pyeongchang Olympics, it was devastating and it was hard to recover from that injury because you need to stay up. If you need to stay up, sometimes you don’t take the time to heal your injury."
"I have to make them understand the mechanics of the jump, but make them understand that if they do that, they're gonna be successful. I show them videos mostly with Yuzuru because I have all the jumps with Yuzuru. I show them that body alignment is the secret."