My brother did sound with Plant for a while in the 80's. He was a big Zeppelin fan and let it be known he didn't like Plant's new direction in music. He and Plant would go back and forth, Plant said" am I supposed to sing Eu yah eueu ya the rest of my life".
During the tour my crazy brother did SOMETHING, another long story, that should have gotten him kicked off the tour. He met with Robert Plant who said he could stay, but he had one demand of him.
So, every night for the rest of the tour, during a Zeppelin song, Plant would hand the microphone to my brother who would off key sing "Eu yah eueu ya".