Thanks for all your responses. I am really gratified to see all this passion for flighted birds, as that is also my feeling. All our birds are flighted.
I don't think I made my question clear. There is no question that we intend to allow Moussa to be flighted. But he had already been clipped at the store. This clipping was done taking only part of the feathers, leaving a sharp, stubby end. Our vet worries that these sharp, stubby ends could be an irritant to a bird, and prefers to take the feather off at the shaft.
I don't want Moussa to experience irritation from these feathers and possibly problems. But he can fly pretty well with this partial clip, and I don't want to inhibit the ability to fly that he has now. Either way, we will let these feather grow back and not clip him again (which it sounds like will take about a year ... sigh)
I really wish they hadn't clipped him at the store. To give them credit, they did ask me if I wanted him clipped or not, but then realized that he had already been clipped, since he was the older of the babies. I could have chosen an unclipped baby instead, but Moussa just charmed me with his personality and I fell for him ... what can I say?