Why people don't use Enemies Maimed by you take #% increased Damage Over Time ?

Am I missing something or not understanding it? I'm playing the gladiator corrupting fever build and feels like a no-brainer to use those gems. That should be an easy 5% more damage per gem. However I don't see anyone on poe ninja using it and the PoB doesn't account it as damage increase.

What am I no understanding here? Is it bugged, does it work, if not why it doesn't?

You might need to check in PoB, enemy is maimed. Otherwise PoB is not perfect, it might be leaving it off.

It is likely they don't take it simply because other gems are more efficient.

As they are probably running pride and vulnerability, enemies already take 80% increased physical damage, so the gem is actually;

(1.85/1.8) = 2.7% increase in damage

If they also run Maim support on Flesh and stone, its another 30% increased damage take, so the gem is

2.15/2.1 or 2.4% increase in damage.

Damage taken is additive with itself, and multiplicative with your own increased damage, damage over time multiplier, flat phys damage on corrupting fever, etc.

Meaning you get diminishing returns if you already have a lot of "Enemies take x more damage", which phys builds do.

Consider you can get up to 16% increased damage over time multiplier (phys and global combined) on a gem.

If you already had 70% dot multi, that would be a 9.4% increase (1.86/1.7). Much more efficient than the maim one.

Even if you stacked a good amount of dot multi, and had 120%, then it is 2.34/2.2 which is 6.4% increase.

Thanks, that explains it. Didn't know increased damage taken mechanic has diminishing returns