Mercenary Curse Limit - Not casting curse despite increased curse limit

I have a kineticist merc with elemental weakness as one of their spells, I have them equiped with anathema to increase curse limit to 3, they have a curse on hit with conductivity ring, and I am using a mark on hit myself.

The behavior I have noticed is that occasionally the merc will open with elemental weakness off the bat, but if the targets have any other curse or mark they will never cast elemental weakness. This makes the spell effectively useless since you most want it on bosses and rares but it will almost never reach them before me (flicker). When they do open with the spell I have verified all 3 curse/marks do get applied.

Maybe this isnt a bug and is intended behavior, but I would think a better implementation even if it cant recognize the higher curse limit would be to force the merc to cast its curse after a certain duration so that it makes use of its full kit.

Same thing here, my merc has frostbite but barely ever casts it. If it simply immediately cast on rares and bosses it would be so much nicer.

Also having this same issue

Yep exactly, glad I looked this up and see that others are experiencing the same thing because I thought something was off!

Same thing here. I gave my merc Vixen's Entrapment to increase her curse limit to 2, but after I cast elemental weakness, she does never cast frostbite anymore.

+1 Same prob but the super strange part is it worked on 2-3 other mercs I had before including the same archtype (kinetic blaster) and others. But I upgraded with a stronger one and she just doesn't seem to get it. Was super smooth before, no issues.

Same problem here.
I have an infamous Stormhand with conductivity in its skillset and Elemental Weakness curse on hit corruption implicit on its gloves + Doedre's Damming.
It does apply Elemental Weakness but never uses its conductivity skill...
I did try to remove the gloves from the merc while the monster is cursed with Elemental Weakness (Applied by the merc) and now it uses conductivity and succesfully apply the second curse simultaneously. If I reequip the gloves on the merc, the conductivity disappear after its expiration and is never reapplied by the merc...

Same issue here, got thunderquiver + 2 Doedre's Damnings and assassin's mark. She only casts her mark when there are no curses on the target, meaning if I have hextouch or blasphemy up she does pretty much nothing. If I put Oskarm on her it also doesn't trigger.

I suspect the AI just doesn't have anything in the programming that considers increased curse limits. Before mercenaries, the only AI entities in the game that had +1 to curse limits (the monsters ancient suffering and ancient wrath) got around this AI flaw by having their curse be an "on hit" passive instead of casting the curse, themselves.

No other AI entity in Path of Exile ever had to deal with considering +1 curse limit on them, and thus mercenaries are in a similar boat until the devs go out of their way to change the AI to consider increased curse limits.

Same issue with the chaos and cold caster merchs. This makes curse skills on merchs pointless. This is 25% of skills of my merch and 90% of the reason I wanted to hire her.
Not even bane applies the curse while saying it apply all curse skills of the merch or does she not use bane then aswell?