I could be way off base here but here is how I have always interpreted conductor sizing for motors......
- The motor BRANCH CIRCUIT conductors must be sized to a minimum of 125% of table FLA (14 AWG in this instance)
- The tap conductors to the 30 amp fusible disconnect switch must be sized to the maximum potential of the disconnect switch ( # 10 AWG for this instance)
Some confusion comes into play regarding the term "BRANCH CIRCUIT CONDUCTORS". NEC article 100 defines "Branch circuit" as the circuit conductors between the FINAL overcurrent device and the load. This means that the only wires that can be 14 AWG in this case are the conductors from the load side of the fusible disconnect through the controller ( if there is a separate one) and to the motor itself. Here is where I feel it can get a little hairy.... suppose I feed this same motor from a 480 volt panel 150' away, protect it at the panel with 30 amp circuit breaker, then use a NON-FUSED disconnect switch as my local means of disconnecting the motor. NOW all of a sudden I can use 14 AWG all the way from the panel through the entire system since the "last point of overcurrent protection" is in the panel. This has always seemed a bit silly to me.
To the OP's original question, I agree that the tap must be # 10 to the 1st point of disconnect since he is using a 30 amp fusible disconnect but... if he was to put that disconnect near the tap point and an additional non-fused disconnect near the motor, # 14 AWG can be used from the fusible disconnect switch through the balance of the system.