Spell/talent mechanics?Follow

With the upcoming changes to certain mage-talents and spells, I realised while doing some math, that I actually was very often not sure in what way exactely certain talents affect certain spells.

I will give you a few examples to show you what I mean by that:

For example I am uncertain if talents, that increase the base-damage of a certain spell by a certain percentage, namely firepower (10% more dmg) and spell impact (6% more dmg) will actually increase the damage of fireball by 16% together, so it does 1010*1.16=1171.6 average damage, or if it will do 1010*1.06*1.1=1177.66 average dmg.

Playing with the fire's tooltip implies that it will increase the dmage of a spell AFTER Spellpower was added to the spell's total dmage, but is that true? This for example will make a pretty decent difference, seeing how a raidbuffed SP-peak of 3k is pretty possible. Even more so, when we look at Ttw, will it increase the base-damage of fireball, or the damage of the entire spell AFTER SP was added? And if the latter is the case in both cases, will the talents work additive and increase the whole damage of the spell together with SP by x*1.15, or will it be increased by x*1.12*1.03?

All of this is relevant to determine if FFB will actually be anywhere near the dmg of 18/53/0 FB spam. FB has the higher base-damage, and eventhough you'd need to drop quite some critrating for hitrating, a mage would get to use the FB glyph (5% more critchance) and any other smart mage would cast focus magic on you, as well as you would do so on him, resulting in an additional 6% nearly permanent critchance. Compared to the FFB mage with his glyph thats 9% higher critchance, making hot streak do more damage as well. So as soon as I know how all the talents actually increase the damamge of fireball, especially Ttw for the most part, it should be reliably predictable how far FB will pull ahead of FFB.

Well, I tried there, but I cannot post there for some reason, and frankly, the Mage discussion about stuff like this is 175 pages long, and starts in late TBC, so I just though if someone knew it right off the back I could just throw it here, I am really sorry If I'm just too stupid to find it for some reason, but I just though it could never hard to summ it up again, so ppl who want the info don't have to digg it up from 175 page long threads.