Feather dusters can loose their crowns, but they shouldn't do it regularly. They do not shed. Provided that the worm is still alive it will grow the crown back. As stated above, it takes a couple of weeks for a full crown to form. It will initially be smaller, but it will come bush out slowly until it is as big as before.
For those of you with small shrimps in your tank you may want to keep an eye on them, they will tear the crown right off in short order. Especially Peppermint shrimp it seems.
It isn't really necessary to target feed with a baster or even to add DT's all that frequently. A couple of times a week will suffice well. Most can do fine off of whatever is floating about the water currents and don't necessarily require supplemental feeding.