Too many smiles, perhaps?
I suppose that "Preaching in the entire inhabited earth" also means 'Preaching in the entire inhabited Internet' because the Earth contains the Internet, a hive-mind of iCyborgs and eHumans, in one big ol' insane A.I. internecine.
On a milder note, we must all remember to put ourselves in a non-biased frame of mind at all times to come to correct conclusions, which applies to all things, whether we are religious or not. For instance, I am religious based on my studies on metaphysics, but I only came to such a conclusion because I weighed what I had learned and I was completely sure on what I had discovered based on Super Symmetry and Super String Theory (and also coming up with other possible formulae) and how it fits in with literal translations on some scriptures. Of course, I'm going to talk about my discoveries and therefore my religious foothold, but I'm not going to ram it through your stomach and into your lung.
True Jehovah's Witnesses don't ram it through your stomach and into your lung, because another scripture must be obeyed relating to being peaceable with all men. The very foundation of the organization revolves around obeying all lessons from the Bible, and to actually know what is in it in order to apply it, because knowing what they should really be doing is important - which all people can relate to in one way or another.