How the hell does Mark of the Abyssal Lord even work?

replaces attribute with an unrevealed modifier of a HIGHER tier.

ok. so im doing some experiments:
body armour ilvl 82
it had flat Life Tier 2 (ilvl 75 attribute), so i abyssal marked it, desecrated with a rib. expecting to see some +75ilvl attributes,
but here none is of that!
first and second one is ilvl 65, cold res is ilvl 50.



What is going on here? I cant find any reliable information online on how it works. Reddit is full of questions and there are zero answers. Alot of claims that the description is a straight lie or its bugged...
FIX the darn description already

unless you mean higher tier of the essence's tier which is ilvl 1 i assume... then that makes sense. But its confusing mechanic or description regardless...