Pleasuredome,
I don't want to seem like a conspiracy nut, but as a student of a Rosicrucian order, I must admit I have seen many signs that the Witnesses have been influenced in their development by someone who had at least a little contact with one of the RC groups. The tetragrammiton is imporatant in RC symbology. Al of this information is of public record among the RCs. Here is an explanation of the symbollical importance IHVH has in the western esoteric tradition: http://www.crcsite.org/tomb.htm (an informative, candid site by the Confraternity of the Rose Cross). www.crcsite.org also has a lot of information on other symbology as well. You don't have to agree with it, and most of it is in the historical perspective, but it is still interesting reading.
Other things which are interesting is that in the 1870's, Rosicrucian activity was fairly high in Pennsylvania. Pennsylvania had a Rosicrucian activity going as far back as the colonial period, but in 1879 Societas Rosicruciana Civitatibus Foederatis was formed. This order, unlike most, requires it's members to be Masons (and of 32nd degree.) It still exists but is very small, with only a few hundred members, compared with a claimed hundreds of thousands by AMORC.
The larger Pennsylvania group of interest would by the one with the Beverly Hall headquarters at Quakertown, PA. Fraternitas Rosæ Crucis, www.soul.org. Here is a picture of one of their buildings.
notice the symbol over the door. This group formed in 1912 (and reformed in 1919, I think) and is still around today, although from what I hear they are beyond the mainstream. The problem for trying to link Rosicrucianism with the Bible Students/Watchtower, is that there is no real homogenous Rosicrucian group. There are many groups, some of which only last a little while. Some are public, others are not. Some are religious and others are less so. On top of that, some are Christian oriented, others are Masonic, others are Golden Dawn, while still others like AMORC have become more "New Age." Many have bogus claims.
I am just speculating, but I believe that the Witnesses have had ex-Rosicrucians among their members back at the beginning. Russell was starting a whole new side-branch of Christianity and he needed symbollism. He used what he had in stock, symbollically, but developed his own teachings. Rutherford, by comparison was an iconoclast (and a drunkard, womanizer, and general bastard). Since then images keep cropping up. Ray Franz hasn't mentioned any kind of initiatic ceremony among people at the top in WTBS, so I would think that possibly people in the writing and art department are just doing their own occult research in the name of looking for things to print, or else some of them are first genreation witnesses with a prior background in western esotericism. This would be likely. I know several elders who were formerly masons.