have strict rules on when I fudge and to what degree. They favor no player over another and never favor me. That's impartial.
I'm actually quite curious about this.
Firstly from a definitional point: If there are strict rules then (known to the players or not) it's not really fudging - it's just application of a rule ie Adjudication. For ex. If the rule is (completely arbitrarily just for ex.) every time a d20 rolls a 11-12, I treat it as a 13 - well ok. I don't think that's fudging if it's a strict rule and it's simple adjudication of that rule!
But second, what warrants strict rules on changing the result? Is it something like: If a creature with multiple attacks rolls a crit, I only count 1 of the attacks as a crit?
Genuinely curious.