This video explains how researchers have found lies are effective propaganda by using the following methodology:
High volume of lies
No commitment to objective reality
No consistency/changes all the time
I think it's interesting in how it relates to cults in General and Watchtower in particulAr.
They make it appear that the truth is "just a position". Just an opinion. The video relates it to modern politics but I see how the same is true of wtbts.