The reason for the master/slave design is that the designers intended to facilitate the implementation of complete Bluetooth chips for under $5. The consequence of this decision is that the slaves are fairly dumb, basically just doing
whatever the master tells them to do. At its heart, a piconet is a centralized TDM
system, with the master controlling the clock and determining which device gets
to communicate in which time slot. All communication is between the master and
a slave; direct slave-slave communication is not possible.