To a certain point I agree with the CO's and DO's. The average rank-and-file JW does not look at 'apostate' sites and is trained not to believe anything negative about the ORG no matter how much evidence is presented. Likewise with doctrinal discussion - the average JW simply believes the GB and trusts them to know what is right when they become confused. So many object to 'deep' studies and 'hard' WT articles and close off their brain if the language fails to match the average intellect of a ten-year-old.
However, they are wrong that such sites do not have a major impact. Those with doubts already are more likely to leave when they investigate the JW's on the Internet. It is unlikely they will be DF'd for apostacy. More likely they will fade away. And potential converts are given access to information the JW's used to be able to hide. I am sure many studies stop following Internet research.
I am currently preparing an 'apostacy' site. My target will not be 'blind' JW's, but those with the brain to question.