ToME: the Tales of Maj'Eyal

I have a tier 5 artifact belt A with

Damage shield penetration: 35%

And an tier 3 ego-belt B with
Changes resistances penetration: +13% physical
Changes damage: +14% physical

when exchanging A for B, I see when inspecting myself:

Attack
Damage modifiers: physical +14%
Damage penetration: physical +13%

and no other differences. Where is the 'Damage shield penetration' value displayed?

Am I correct in guessing belt B is good against any enemies, but belt A is better (since 35% > 14%+13%) against enemies with a damage shield?

dam shield pen is not displayed on char sheet

Belt B is only better if you are using only physical damage.
Otherwise it is quite possible for Belt A to be better, as damage shields are quite common and you don't have to break a damage shield before you can kill an enemy.

having dam shield pen can lead to lower DPS though.

Explanation, Ithuriel was the one to report the bug iirc :
let's say you deal 1000 dam. The enemy has a 100hp shield. You have 50% dam shield pen.
You will not deal more than 50dam to the enemy. Your damage appears to be capped to the % of dam shield pen.

I'll edit with the link as soon as i find the report again.

Cathbald wrote:having dam shield pen can lead to lower DPS though.

Explanation, Ithuriel was the one to report the bug iirc :
let's say you deal 1000 dam. The enemy has a 100hp shield. You have 50% dam shield pen.
You will not deal more than 50dam to the enemy. Your damage appears to be capped to the % of dam shield pen.

I'll edit with the link as soon as i find the report again.

How long this bug exist? Is it new?
Otherwise it looks like dam.sh.pen used by players very, very rarale.