[just another ref]

After a long and thoughtful consideration, I have decided that since there is no published definition of what a "defensive player" is, each of us must make up his/her own mind and proceed accordingly. Forget team control for a minute.
On a throw-in, team A has the ball, therefore they are offense. So, conversely, team B must be defense. The way I see it, they will continue to be defense on this play until they gain control of the ball or until a shot goes up. Therefore, if B2 leaps from FC, grabs the ball and lands in BC, I believe I will continue to consider this a legal play until a casebook play comes out which states something different.