Ok. Uploading screenies with destruction perked to Intense Flames and Illusion perked to Rage.
http://cloud.steampowered.com/ugc/594703156257669449/213108E4476570E02B631B678715A737A557778D/
http://cloud.steampowered.com/ugc/594703156257671987/CE8708051BA1EBE80BE16BC24134B78A5E597C5C/
http://cloud.steampowered.com/ugc/594703156257674817/645DD08197E25669273249F6BD81C7D5FC07907F/
http://cloud.steampowered.com/ugc/594703156257678352/07F1BBD3C02F0BFB61F7026BE433D22A7DAAC5AC/
http://cloud.steampowered.com/ugc/594703156257680934/65924FB11F1583225F297AAF0C8ED6413F81A5EC/
You mean Aspect of Terror, right?
Ah, now it makes sense. Aspect of Terror adds +10 levels to the effectiveness of Illusion-school Fear spells. It adds 10 damage to all Fire spells that are capable of inducing Fear in opponents.
I'm pretty sure this isn't intentional on Bethesda's part, although I may be wrong. In any case, 10 is a very small difference to a 150-damage spell. It won't make Destruction suddenly become powerful at high levels, although the boost to lower-level spells, particuarly Flames, is pretty good because 10 is a higher proportion of their damage output.