Fedor has worked under Johan Ruysink supervision a lot in the past. And this brilliant Dutchman is a proponent of such a stroke I recall. In order to achieve a full-length follow-through for a proper draw shot (which would be also smooth), you simply can not do without the elbow drop.
Of course just another moving joint added to the stroke is not going to provide any benefits to a player if his stroking motion has any, even little, flaw. Great fundamentals is a must, and everyone who has worked with Mr Ruysink knows that.