Learn English – When to use “1” vs. “one” for technical writing

It's better known, and more often used, as the abbreviation NB. Expanded, it could indeed be taken as pompously using Latin for the sake of showing off that you know a Latin phrase.

In other contexts I'd worry that some who know NB might not know Nota Bene. That's probably not a great concern in a masters' thesis, but it's another reason to favour the abbreviation, generally.

As @ChrisSunami says, if a person judging or grading your paper says "this is the standard", then I'd follow that standard. You could find some authority that disagrees and argue about it, but what would you gain? Even if you forced the person to concede, he might then be annoyed with you and be looking for ways to mark you down. There's no point starting an argument that you really can't win. Just follow the rules you're given.

There are two easy ways to avoid using "I" in a paper:

One, use passive voice. "Suggestions for performing cognitive workthroughs were received ..."

Two, personify the paper. "This paper presents several algorithms for ..." rather than "I present several algorithms for ..."

Oh, a third option occurs to me. I've read technical papers where the author refers to himself by some sort of description in the third person. Like, "The researcher performed several experiments using flux capacitors ..." This is especially true when there are several authors, or one person describing the work of several people. "The researchers investigated ...", "The team considered ...", etc.