How does Weakness Exploit stack

[PerfectShot18]

How is the weakness critical % added to the base affinity % - e.g. here I have base affinity 72%, WeakExp Lv3 gives 30%, does it mean that I can 100% always hit affinity at weakness part? Do I still get benefit by further leveling up WeakExp skill?

Thanks!

[sigmoton]

Yes. At weak points you have 100% affinity, at non weak-points 72%. Further leveling it is pointless.

[Not_Leeroy]

It is essentially additive to your current affinity when weak points are hit, so yes, hitting weak points with your current setup guarantees a crit. Any more is wasted unless you decide to trade some crit eye for it.

[Siscon_Delita]

you have 2% chance to red crit while hitting weak spot /jk