I've seen worse too Ricky ~ woman did the same thing to my mother once. Unfortunately she wasn't able to stop in time even in a genuine 30mph zone resulting in a fairly substantial crash writing off two cars. Luckily no injuries.
Anyway it was bad driving from the BMW driver imo ~ why not wait 30 seconds and pull out after Mike had driven past?
Just in patient, bordering on dangerous driving, ...again only imo.