I am always wondering if the work areas affect NC.

What you got from your investigation reinforce what I thought:

Work areas do affect name check.

In order to get I140 approved, I used some words like, "bio-defense", "anti-terrorism", etc. sensitive terms to argue that about NIW qualifications. My I140 got approve within 1 month after it was filed.

But now, my NC has been pending for more than 2 years. Just got letters from FBI through senator, it seems no help by writing senators.