It's not the item indurance but the fact that the game on Siege is less item based.
Our balance between damage and healing is different than on normal shards. A nerf to healing will make it worse as our defense is low already, special vs upper pets.
This changes are based on players using ubber gear and maxing out the mods
If you are not running with 5x70 resist and alot of mods to make you heal faster, gain mana faster, give you better defense, lower your targets defense, deal more damage, hit better etc, this changes may fail badly and destroy the balance instead of fix anything.
Best way to test stuff like that is on a copy of your shard on TC where you and your enemies all are using items and templates normal for your shard.
Alternative, add Siege code on TC = no item insurance, 1 siege bless uptions, Siege armlore, no auto detect, no gating out and in dungeon / Ilshenar. Siege vendor rules = vendors won't buy items and won't sell resources.
No blessed factions items, I'm sure I forgot something.
And when we are there, lets test no greater dragons, a nerf to stealth no instance corpes, but good old going grey when looting without looting right.
Also we need to be able to cut up bodies again, we need our shard labeled Mature.
We keep getting code bleed over from trammy shard without it being tested for Siege. Alot of the last we had got had been ok but this balance thing really need to be tested for Siege or keeped of Siege.
A way to test it could be, letting us have it on the shard for 2-4 weeks and if it do not work, remove the changes again or changes them to fit Siege.