Who do you think these guys are writing to? Are they addressing the scientific intelligentsia of this world or the religiously superstitious?
When a supposedly educated literate country like the USA has people who think the world was created in six days just a few thousand years ago, what difficulty will the WTS have convincing those of less advanced countries? Or does the WTS want its US citizens to have the same level of education as those of a Third World country?
Doug