The learning state is not really useful, even with STP;-)
Basically, RSTP was built on the top of STP. If the RSTP enhancements are not applicable to a particular scenario, RSTP just behave like STP.
So for example, on a port with no neighbor and not identified as edge, the transition to forwarding will be slow, exactly as in STP (and you'll have a learning stage). Also, if an RSTP port is connected to an STP port, there will also be slow transition using the learning stage.
It's true however that in a network adapted to RSTP (p2p links, all devices running RSTP and edge ports identified), the learning state should not be used.
Regards,
Francois
