Okay, all of a sudden while I'm in a dungeon roasting some Draugr, my fireball starts doing noticeably more damage. I pop into my magic screen, check the spell, and lo and behold, the damage of all my fire spells (except for Fire Rune, Flame Cloak, and Wall of Flames, which cannot have their damage boosted by anything anyway) has been bumped up by about 12 points. It's as if I had taken the second rank of Augmented Flames, Which I have yet to do. I stripped off everything I was wearing, and the damage stayed boosted. I checked my active effects page, and I can't see any reason for it being boosted. I don't know what's going on here, but I like it.

Come to think of it, has anyone else seen the loading screen tip that says something like "Magic spells will only improve when used against valid opponents."? That one always confused me, but maybe your spells improve with use? If so, I will officially kiss Bethesda's feet.

I think they just mean that destruction can only be leveled if it does damage to something. Not just when casted.

Have you perked Illusion to Aspect of Terror?

I tested some today after some forum posters asked me to and it buffs fire spells a little.

A perk in the illusion tree that improves vs fear effects boost the damage of fire spells by 10 points.

Are you seeing numbers similar to mine in this thread?
http://www.gamesas.com/index.php?/topic/1275185-flames-and-firebolt-damage-is-too-high/page__st__20__p__19298514__fromsearch__1#entry19298514

http://i43.tinypic.com/103egx4.jpg

I have no idea what happened to mine, the damage just went up on some fire spells about a week ago.

I do have aspect terror perked.

I uploaded some screenies from my tests earlier today:
http://steamcommunity.com/profiles/76561198052221188/screenshots/?tab=all

Check those to see if numbers match. That is with 2/2 Augmented Flames and Illusion perked to Aspect of Terror.

No enchants or potions used. It was my warrior character with 0 magic advancement, I used the console commands to get 100 destruction and illusion.

Ah, that must be it. I just got that one today.
I'm guessing the game counts fire spells as fear spells, regardless of whether or not you have Intense Flames yet. I'm betting the effects of Illusion perks are just a straight +x% effectiveness.

EDIT: Hmm.... So with Augmented Flames 2/2 and Aspect of Terror, Incinerate's base damage is 100. Dual cast, and that's 220 a pop. With Expert Destruction and Impact... Geez... And that's not even taking into account burn damage and damage bonus against burning targets.

It was a 10 damage difference without augmented flames.
It was a 10 damage difference with augmented flames.

Haven't tested with full enchants and stuff because I like to pretend I have a life.

Well, those kinds of effects work off of the starting percentage. As in, they're all applied as a single big percentage instead of separately. Can't for the life of me remember the mathematical term for that.

Although, come to think of it, all of the spells were boosted by exactly 12. I guess it's a direct increase.