As far as I know, Brad still works as a choreographer... which is how he met Stevie (when he was called in to choreograph the second version of the "Stand Back" video).
Stevie spoke highly of him, and apparently liked him enough to also feature him in the videos for "If Anyone Falls," "Talk To Me," "I Can't Wait," and "Rooms On Fire"... as well as bringing him on Saturday Night Live with her, and the 'Rock A Little' tour.
He's also worked with Madonna, and has choreographed the dance sequences in films like 'Back To The Future' and 'The Beverly Hillbillies.'
He also had a bit part in 'Grease 2.'
In more recent times, he choreographed a Tim Rice musical, called 'Heathcliff' (of 'Wuthering Heights' fame), and I believe he served as Yoga instructor for Stevie's 'Shangri-La' tour.