Demonic Knowledge: Increases your spell damage by an amount equal to 12% of the total of your active demon's Stamina plus Intellect.

What steps will reproduce the problem?
1. Look at the tooltip for an item with Stamina and Intellect.
2. Equip the item, and look at the change in Spell Power

What is the expected output? What do you see instead?
Spell Damage in RB's stat summary does not match the change in Bonus Damage on Blizz's Character UI.

What version of the product are you using?
## X-Curse-Packaged-Version: r269

Please provide any additional information below.

70 Blood Elf Warlock

Base Stats, No Gear, No Pet:
81 Stamina
137 Intellect
0 Spell Damage

Felguard:
322 + 69 Stamina  (85.2% Inheritance)
152 + 47 Intellect  (34.3% Inheritance)
+70 Spell Damage from Demonic Knowledge

With Gear, No Pet:
390 Stamina
334 Intellect
937 Spell Damage

Felguard:
322 + 335 Stamina  (85.9% Inheritance)
152 + 115 Intellect  (34.4% Inheritance)
1047 Spell Damage, 110 from Demonic Knowledge, an increase of 40 from gear.

RB predicted bonus from Demonic Knowledge for my gear: +18 Dmg; Less than half of the actual increase.

If we assumed pets get 30% of their master's Stats (as I also read on wowwiki)
Stamina: 309 * .3 = 92.7 Pet bonus from gear
Intellect: 197 * .3 = 59.1 Pet bonus from gear
(92.7 + 59.1) * .12 = 18.216  <-- This is the incorrect value RB calculated

However, if we look at the actual bonuses my pet got on the pet tab of Blizz's character panel
Stamina: 266 Pet bonus from gear
Intellect: 68 Pet bonus from gear
(266 + 68) * .12 = 40.08  <-- The is the bonus my Spell Power is actually getting.

Conclusion:
Warlock Pets gain more from their master's stats than either Wowwiki or RB think, particularly stamina. As a result, warlocks are getting more spell power from demonic knowledge then RB predicts. Unfortunately, my warlock is only level 70, and doesn't have enough stamina or intellect to give accurate values for this scaling. I'm going to keep leveling, of course, and will help out with more data whenever possible.

Addendum:
I just realized why the observed inheritance values seem strange, I neglected to consider Fel Vitality (Increases the Stamina and Intellect of your Demons by 15%), this also applies to the gains from the master.

390 Stamina * .75 (75% Inheritance) = 292.5; truncated to 292
292 * 1.15 (Fel Vitality) = 335.8; truncated to 335, exactly the observed value

334 Intellect * .3 (30% Inheritance) = 100.2; truncated to 100
100 * 1.15 (Fel Vitality) = 115, exactly the observed value

So the actual scaling is:
1 Stamina on gear * 1.1 (Demonic Embrace) * .75 (Stamina Inheritance) * 1.15 (Fel Vitality) = 0.94875 Pet Stamina * .12 (Demonic Knowledge) = 0.11385 Spell Power per Stamina
1 Intellect on gear * .3 (Intellect Inheritance) * 1.15 (Fel Vitality) = 0.345 Pet Intelligence * .12 (Demonic Knowledge) = 0.0414 Spell Power per Intellect

And all the numbers work out. Well, almost. Because the stats are truncated at each step, the actual values will be slightly less than calculated by my 'scaling equation' above. The only way I can see to get the true bonus is to actually work through the calculations.