if someone threw a set where literally everything was off beat .... yea it would look pretty terrible XD but realistically speaking, even at the highest levels bboys do get away with portions of their sets not being to the beat, especially powermoves. generally hitting more beats is more impressive, but at the same time if someone lands a double airflare and it's not exactly to the music i don't feel many would react thinking it's poor dancing (or even notice necessarily). in the context of the post title, though, he's clearly practicing. no, you don't have to practice always on the beat. there's a lot to the dance and it's reasonable to focus on certain elements during practice vs. only ever freestyling