Doesn't the article mention anything about their basic core doctrines on the trinity, soul, hell, etc, as being the main reason why they have 'da troof'? In other words, their claimed lack of all 'Babylonish, pagan-derived' doctrines? In all my 40 or so years as an active borg those were the things I usually mentally fell back on that made me think they were right.
I always new the Christadelphians also rejected the trinity, immortal soul, hellfire, but then I distinguished my religion as being superior to the Christadelphians because the latter were tiny in comparison and far less international than the JW.s We would expect Jehovah to have a large, international 'congregation' of people preaching worldwide, I reasoned to myself.
Fallacious reasoning I know, but that's the bottom line of how many JW's think.