Parents everywhere got a measure of their culture relevance last night, when avant-electro chanteuse Grimes performed “Genesis” on Late Night with Jimmy Fallon. Those who stayed for the entire song were rewarded with an explanation of a hashtag’s function on Twitter, and those who actually enjoyed it were tattooed with a cool symbol that their teenager would respect them for, both courtesy of General Electric. Grimes appeared looking like the ghost of ’70s she-samurai and flanked by two energetic black slip-donned dancers, the ground around her littered with matter that’s either flower petals or feathers left over from Fallon’s popular “Put A Bird On My Head” sketch. A strong TV debut, but the question remains: Will Grimes’ cathartic and exciting electronica influence the mainstream? Are we all going to be that parent in 20 years, explaining to our children the similarities between “Genesis” and some pop hit composed by a sentient blender? Better pick up Visions and get well acquainted with her work before all that.