TIL when Primus played their song "My Name is Mud" at the rainy Woodstock 94, the crowd responded by pelting the band with mud. The band's singer, Les Claypool, stopped the song and said "when you throw things on stage, it's a sign of small and insignificant genitalia." The crowd ceased throwing.

I'm a big fan of Primus (a friend into bass introduced them to me in 1988. When I heard them used on South Park, I couldn't believe it/was thrilled)!
But if you are going to play a song called "My Name is Mud" to a muddy Woodstock audience (after the rain, everyone is covered brown and enjoying a large friendly mosh-pit in front of the stage)... 1. you should wear a poncho for the song 2. not play the song in the MIDDLE of your set, consider it at the end.
PS- Here is the video. I don't hear OP's quote. What I hear is, "Boy I opened a big-ass can of worms with that one, didn't I?! The song is called 'My Name is Mud', but keep the mud to yourself, you son-of-a-bitch (said in a playful tone)." (They use "son-of-a-bitch" in lyrics too, so not as angry as you might imagine.) And they carry on without any problems.

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