The Miami Class B has a problem. There’s a seldom-followed regulation, 91.131(a)(2), saying large turbine-powered aircraft—essentially a King Air 350 and larger—operating from a primary Class B airport, must remain in the Class B airspace. The problem in Miami is that many aircraft descend below the floor of the Class B.
The FAA’s solution isn’t education or even enforcement; it’s expansion of the Class B plus an unrelated expansion of nearby Fort Lauderdale’s Class C.