A few years back I had a discussion with a friend from the art department who was one of those asked to leave bethel during the budget cuts. When I spoke about subliminal art, he laughed it off saying that what we see are the brush strokes of a tired, over-worked painter, who has done his 19th editing of the image. Adding something subliminal would not even occur for an artist working at WT.
I don't believe this hidden message crap. what will WT achieve by adding these to their publications? What is the message that they are trying to convey? Since some of these images are from the 70's and 80's, did Fred Franz say something about it, since he was in the GB? Would an average JW have the mental skill and the time to find these hidden messages, among all the constant drumming he has to go through. If it is intended for a few people, then it doesn't make sense to publish it in a public WT.
To discredit the WT, we need to look for the obvious visible flaws, which we have in abundance, and not subliminal images.
Brushstrokes create patterns, and patterns may create anomalies, which are quite prevalent in the graphic artist's world.