[quote=@Lugubrious]
So if Protesters was only passed by the slimmest of margins, then it's A-rank, and worthy of 4 credits.  Mission antagonists only get 3 credits, regardless of the mission's actual difficulty
[/quote]

I thought since S was extremely difficult then that meant the scale was:
A: Easy
B: Medium
C: Hard
D: Difficult
S: Insane
SS: Lunatic
SSS: Suicide

I was under the impression that C is what would earn four credits so I think a translation with the actual system in mind would look like this:

[quote]
I don't believe that qualified as a A rank. In my opinion is was barely a B but that's just me.
[/quote]

Bearing in mind the system as it is actually set forth (thanks Lug) by RWBY standards I don't think it unreasonable to assume that level of danger is what is expected of hunters-in-training on a standard day. Cause of the involvement of the White Fang I think it was step up from a C but not challenging enough to be a B. I think it to be around a C+. I don't know what that means for your credit score but I don't believe it ranked an A (what you gave yourself) which is supposed to be difficult even for seniors.