Excellent observations, Mebaqqer. I never noticed that inconsistency before, although I honestly have not read the NWT much since I left. I am sure there are many other interesting examples out there. BTW, welcome to the forum!
Thanks to the new search utility, I was able to find this interesting old post in the archives:
I recently had a discussion with an ex-DO, and Gilead grad who met with F. Franz in 1958 to discuss his concerns with the translation of the preposition "in" ("en", Gr.), which F.F. translated seven different ways in the first two chapters of Colossians. After three hours of discussion he said F.F. was unable to answer any of his questions. He felt that F.F. had at best a "cursory and superficial" knowledge of Greek.
At least he could have used better English!http://www.jehovahs-witness.com/6/2510/33203/post.ashx#33203
oompa....The NIV is pretty good....it is more on the evangelical side. I tend to refer to the NIV and the JB (which is a Catholic translation). Both however are rather loose in their renderings and occasionally veer a little bit close to paraphrase, so I always try to check the original language just to be sure I have not been misled by the translation choice on a given point. I like both versions mainly because they read rather well in current English. The JB also has the best layout and presentation I have ever seen in a translation (and it uses Yahweh in the OT too).