WHEN Damien Hirst’s spot paintings opened at 11 Gagosian galleries worldwide in January, critics busied themselves redrawing many of the familiar battle lines that have helped Mr. Hirst become very rich.

Meanwhile, a YouTube video critique featuring Hennessy Youngman, a video character who wears a goofy baseball cap and layers of gold chains, was going viral in the art world, mixing hip-hop lingo and profanity with high-minded art criticism.

“I understand that, as an artist, if you actually touch your own artwork, the value of said artwork is severely depreciated,” he says wryly about Mr. Hirst’s paintings, which are made by assistants and can sell for millions of dollars.

The video was part of a YouTube series called “Art Thoughtz” created by and starring a Brooklyn artist named Jayson Musson. (The character Hennessy Youngman, he said, is a reference to the standup comic and Hennessy cognac, a favorite reference in hip-hop music.) His roughly two dozen videos on topics like “relational aesthetics,” “the sublime” and “Poetic Waxin’ ” have made him something of a court jester to the art establishment.