1) If BlueWing is an F, it is deeply puzzling how he is able to have such great precision in the words he uses. As you state "He chooses his vocabulary with the precision of a surgeon "
In order to be precise one must be logical, because only logic evinces structure in all things. If one does not clearly see structure in ideas he discusses, he cannot have an exact idea of what he is doing. Certainly there are some Fs with a good handle on the Thinking function, but rare. What makes one an F is the stronger psychological predisposition towards an emotive valuation rather than logical analysis. An F in a scenario like this would most naturally make a value judgment first, (or be tempted to the most), like some Fs have said this is offensive! Secondly, an F would proceed to analyze the matter. Yet BlueWing consistently analyzes before making value judgments. The terms 'vulgar', 'crude', 'simplistic' are used primarily in their most precise linguistic fashion possible, they mean to describe what is to be regarded as a fact rather than one's emotive mindset. Hence, this is a manifestation of a Thinking cognitive faculty more than a Feeling.
2) Alternatively, if BlueWing is a T, he is not naturally in tune with Feelings, therefore likely lacks EQ, unless he is one of the excpetional Ts who excell at activities they are not naturally talented in. He has shown no evidence here of having a high EQ. Thus, because he does not understand how he makes people feel he could not be making the statements he makes specifically to evoke a negative emotional reaction from the audience. As is common of a Thinking type, he is chiefly concerned with understanding reality.
3) "I believe that is also the reason he rarely just expresses his thoughts and beliefs without resorting to quotations and technicalities. It's always easier to hide behind others' words "
He produced an original work on typology.
Principles of Typology
I am not sure what quotations you have in mind, though sometimes I quote Jung to better illustrate my point. I do not let Jung explain my entire idea, I quote him after I have explained my views. I quote Jung strictly to help the reader better understand my message by simply giving him the same message stated in different words. It is an expository technique frequently employed in philosophy and ought to be frequently employed in many avenues of technical writing.
4) "I do not believe an INTP would allow his/her feelings to guide their action and vocabulary choices to this extent."
Where is the evidence that BlueWing is guided by feelings? This is unpersuasive as there is he usually explains his reasoning in tedious detail. I grant, however, that in the case of many Fs who simply do not understand logic, the reasoning flies over their heads. In that case it simply does not matter how clear and thorough the reasoning may be, they just lack the logical aptitude to see it.