We've all been guilty of it in the past. As long as going forward it's implemented fairly among regular posters and mods, it'll be very good. I speak as someone who has modded before when I say that sometimes there is a temptation of an 'us and them' attitude and these types of rules are sometimes not applied to all.
I've 'resigned' (if that's the right word) from boards as a mod once or twice because it's very easy for someone in that position to develop an antagonistic attitude. Not in terms of their opinions but in almost daring a poster to respond to insults knowing that if they do, they'll get reprimanded, or worse. The "so what are you going to do about it?" attitude isn't rare. I likely developed one myself while doing it. It's almost inevitable sometimes so it has to be especially guarded against.
The newbie system here makes that far less likely to happen than most other places though, with the filters for spammers and the rest. it makes moderation less of a hands on issue/necessity