Do 30% boss 15% boss 30% boss stack post chaos or post jump?

That means those vids we saw on kms were chars with 30 20 30 boss % on their equips?

and those 2-3min solos of zak by db were 30 20 30 boss % on their dagger n katara I believe which amounted to 160% boss dmg.

Thx for clarifying, so that means if one would to play db now , a 30 20 30 boss % on their dagger and katara would be the best shot.

Similarly for other characters having a 30 20 30 boss on their weapons.

Unlikely. I can do a 2-3 min run myself with only a 30% on my dagger, and of course DBs have a better single target DPS. They might have had 2 lines between the two weapons, but I doubt many (if any) of those had 3+ lines between the two weapons combined.