https://wow.gamepedia.com/Hotfixes/2009_Archive
April 17 (1st reset) - XT-002 Deconstructor will no longer cast Light Bomb or Gravity Bomb while channeling Tympanic Tantrum.
April 21 (2nd reset) -All of the additional creatures spawned during the XT-002 Deconstructor encounter can now be snared in either difficulty.
April 22 (2nd reset) - The enrage timer on XT-002 Deconstructor has been increased.
April 23 (2nd reset) - The damage of XT-002 Deconstructor's Gravity Bomb ability has been reduced.
April 28 (3rd reset) - The XT-002 Deconstructor encounter has received the following changes: The duration of Tympanic Trantrum has been reduced, the timer for XT-002 to hit berserk has been increased, the damage of Light Bomb has been reduced, the effect radius of Light Bomb has been reduced, and the health of XM-024 Pummeler has been reduced.
May 4th (4th reset) - The health of the Heart of the Deconstructor in the XT-002 Deconstructor encounter has been reduced.
I don't remember if we killed it after the first berserk nerf on the 2nd rest or the large nerf on the 3rd reset, but it wasn't pug friendly until at least 3rd reset. The guild in question had Sartharion 3D on both difficulties and had many 3/6 sunwell raiders. It was really frustrating to get brickwalled that quickly into a new raid. It was obviously more friendly later, but the tier overall started poorly.