The WTS tries to keep it separate but the rank and file jw still thinks of the WTS as the same as the FDS/GB.
The WTS/FDS/GB also wants to give the impression that individual jws make a personal choice to not joing the military, not to take a blood transfusion, etc., deceiving the outside world into believing that nothing bad will happen to them if they make the "wrong" choice. The vast majority of jws will say "the Society (WTS) says" not the bible says or "the elders say."
*** w98 3/15 p. 19 par. 4 Living Up to Christian Dedication in Freedom ***In order to avoid misunderstandings, Jehovah’s Witnesses try to be careful about how they express themselves. Instead of saying, "the Society teaches," many Witnesses prefer to use such expressions as, "the Bible says" or, "I understand the Bible to teach." In this way they emphasize the personal decision that each Witness has made in accepting Bible teachings and also avoid giving the false impression that Witnesses are somehow bound to the dictates of some religious sect.