When the Who did their amazing set that night, nobody knew about the smoke bomb inside Keith Moon’s drum set, especially Wally Heider, who up until that time had placed his set of condensers and dynamics on stage as was the norm.
At the very end of the song, Wally steps into history as he avoids running into a dancing Roger Daltry and dodges guitar-shrapnel from Keith Townsend’s antics as he rushes to save his microphones from certain destruction.