What about factual errors from other sources?
I remember at school, must have been 1963 or 1964, that the teacher told us man would never be able to land or wolk on the Moon. Why not? because since it had no atmosphere, it was covered in a layer of dust some 10 feet deep, so if a person would step out of a space ship of some kind, he would sink deep into this layer and be fullt entangled in it and die.
and another teacher told us about how it was travelling in an aeroplane, that one would suddenly come upon pockets where there was no air, "air-empty-space", and the plane would then fall downwards until it hit air again. And therefore it was very scare when you were in the landing process, if the plane was 300 feet above ground and it suddenly hit upon an "air-empty-space" which was 200 feet deep and therefore would fall direclt downwards 200 feet and stop just 100 feet above ground. Perhaps a very strange way of trying to figure out what turbulence was.
There have been a lot of factual errors down thru the centuries. When WT has produced its share, I feel it has been when they have tried to make Scripture coincide with or support some of the latest scientific ideas - finds which at a later stage have been found to be not quite verifiable.