"So, if you kept rerolling the first mod, a random mod sequence might look like: A > C > E > G > A > E > D > F > C > G > H ...
If I follow Khaylara's decription correctly, she is instead seeing: A > C > A > D > A > D > A > C > A > C > A > C > A > D..."
That's the most accurate description. I underlined part of Tagamogi's post because it is not a matter of narrowing pool and not having mods available. If I get only mods I want on an item with 1 exception and I try to reroll that exception, what happens is what the quote says. Still plenty mods to roll from but the rerolling keeps bouncing between the same 2-3 useless ones.
I just want it to be understood-I am rerolling a chestpiece mods while having other few chestpieces in my backpack so I can clearly see what mods are available. I repeat, it's not a matter of mods not being available it's the fact that some mods seems stuck in a loop. Crap mods only get rerolled into other 1-2 crap mods and nice mods follow the same pattern.
I'd really like Citan's input on this.

