Say my opponent has a Tiger Fury at 26 Damage. If I play an effect that says "Return this attack to it's printed damage" (i.e. Fight or Flight) isn't that just setting back to printed, and not actually reducing because there is no negative? It does say "Return" not "Reduce".
On the same note, there is a scout in my area that has ruled that if an attack is at 0 damage you can use Fight or Flight to reduce it back up to it's printed value. I was awful in math class, but isn't it impossible to "reduce" UP? It's an answer I'd like to print and take to him.