At the end of “Crotch (all the Joseph Beuys references in the world cannot heal the pain, confusion, regret, cruelty, betrayal, or trauma....),” a 2009-10 solo show by the performance artist Keith Hennessy, he sat naked but with his groin covered in lard. He gathered us, the audience, around him onstage. Pushing a needle with blood-red thread through scars in his own flesh, he sewed the thread through the clothing of the three people in the audience seated nearest him.

Wow. And I thought it was hard to leave early when you're stuck in the middle of a row.