Figurine of the Colossus - Stealth nerf?

Figurine of the Colossus is the block heal trinket from Shattered Halls, typically on a large pack of mobs due to it being up for 20s you could expect it to heal you to full with a shield block usage.

As of right now the trinket seems to have some sort of internal cooldown and instead of seeing a full heal over multiple usages the highest I saw was 5.2k, with most usages closer to half of that and the heals coming in very slowly over the 20s. Anyone who has solo farmed ZG tigers during TBC knows the trinket was crucial to doing this, as you would let your health get low (10-20%) and then pop it to heal to full by blocking all the attacks from the non-elite tigers (prepulled before boss), now it’s only a fraction as strong and this method doesn’t work.

ZG Tiger still soloable via brute force dps from WOTLK talents, but it seems the trinket no longer functions and other solo farms are dead in the water as a result.

Was this tested at 70 or 80?

Tested at lvl70.