pbrow, you talk about https://en.wikipedia.org/wiki/HTTP_referer
I have been always wondering if they monitor the referer values for HTTP requests they receive. They can discover apostates, if somebody is logged in jw.org and in the other tab he reads JWN, when he clicks reference to jw.org, they will see brother X.Y. is visiting them from an apostate web.
So those still with jw.org account ( ), be careful!