So, what's the difference between adding 1 damage vs 1 net hit to the total net hits? It arrives at the same destination.
I take the point that you can't buy an autohit on an attack, and that's fair enough, and once you've hit adding 1 damage is the same as having hit a little extra hard (ie rolling one extra hit). It's like an special ammo effect, essentially. "If I hit you with my explosive ammo attack, you take +1 damage".
Assuming any other resisted spell fails to be fully resisted, couldn't you apply the same amp to it? So, "When successful, the spell is treated as having had 1 extra net hit when determining the results"?
Or does that break something?