Warlock Summon: Pit Fiend General

[Aren]

Description of Bug Experienced:
While testing the Pit Fiend General (PFG) on a fiendish warlock, it occurred to me that the summon does not utilize its Improved Invisibility (http://wiki.arelith.com/Summons#Devils_.28Lawful.29). This majorly affects the summons tanking-utility in endgame content, as the PFG has much less DR (10% as opposed to 25%) than the Balor Lord, making the Balor Lord a more attractive choice. I know for a fact, that the PFG used to cast this at the start of combat (and the ability being on a CD) - but after the slight changes to the PFG (equipping it with a sword instead of Mace ect.) this ability seem to have broken.

Steps to reproduce the Bug:
Summoning a PFG, and examining its AI in various combat situations.

Expected Result:
PFG should cast Improved Invisibility at the start of combat, to mitigate incoming damage.

Actual Result:
PFG does not cast Improved Invisibility - it only activates its aura.

Screenshot(s)
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Additional Information/Notes
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