I've only been training a little over 3 years (definitely not a BB), but maybe the BB meant there are many different types of sparring. Many (most?) schools war

I've only been training a little over 3 years (definitely not a BB), but maybe the BB meant there are many different types of sparring. Many (most?) schools warm up, show a move, (maybe drill it), then let everyone spar away. The problem is when sparring the person with more skill will severely limit the positions the less skilled person sees. If the less skilled person happens to be very strong or athletic they can in turn limit the positions the more skilled person sees just by holding on, which turns the sparring into very limited training value. For me, what has helped really learn is drilling. I know lots of BJJ people hate it, but I like winning and drilling works. Even those who hate drilling will admit it. Positional sparring. Start in some position and work from there. I purposely let less skilled people start in advantageous positions so they get to work from a dominant position (where most submissions come from), and I get work escaping from bad spots. Finally, flow rolling, which at higher training levels doesn't look that different from sparring. But, it's sparring where both sides give and get so that each sees many positions. At my level we also move much slower. Think about how hard it would be for someone to learn Chess if all they played was bullet chess? You need that bit of time so that your mind can start to build patterns, and then speed up. I'm fortunate that I lucked into a school that teaches a bit differently. EDIT I should add that free for all sparring still happens, it's just not the focus of every class. Open mat days and end of class is often when people go more free for all.