This has been my experience with my family, as far as doctrinal matters are concerned:
-My dad (now deceased) after 1995. I believe that the Generation caused him to stop attending. But he still went took us to all the conventions, so I think he still believed in all the crap. Up until he passed away in 2000, he thought the end was "just around the corner".
-My mom still believes the 1914-Generation doctrine that was taught for over 50 years. Even after I showed her the 1995 article, she still believes it. This is mainly due to her father (my grandpa), having been born in 1913 or 1914, is still alive and breathing. So to her, she thinks the end will come before he passes away. Oh yeah, and she still thinks the preaching work is for separating the sheep and the goats.
-I'm the oldest sibling, and the next sibling down is my sister who is a Witness and believes whatever the next Watchtower teaches her. That's it.
-After her is my youngest sister, and I've shared with her a lot of "apostate" things. I want her to realize what the Watchtower really teaches before she tries to get baptized. She's doing well, but she's conflicted because she still lives at home with my JW mom. She's still trying to grasp everything I've taught her, but before I started telling her everything, she barely knew anything.
-My brother-in-law (who married my first sister) didn't know that the Watchtower teaches that Michael the Archangel is Jesus. He didn't know that the Watchtower claims they were picked in 1919 as the only true religion. He didn't even know that Jesus wasn't the mediator for the great crowd! But he is pretty gung-ho about being a Witness and going door-to-door.
I'll be honest. I didn't know much about anything when I started researching. Even though I was a Witless for most of my life (until recently), I never took the time to study all of the old crap. And the old crap never gets brought up anyway, so I was plain ignorant. The one thing I'll never understand is how full-grown adults can accept all of the changes that have occurred over the past decades. I'll never understand that... I guess when you think that the Watchtower is truly guided by God, you're willing to accept anything.