Tandem Assault Usage?

Hello,

I was looking for tandem assault notable passive in POE2, and i can't figure it out how does it work.

I mean, the AI of the companions are very small developed, my companion is aways on my side on fights and does not engage on enemies by itself (as a enemy monster would do, this could be like this...), and they almost fight all the time in close range to me and enemies (by this I mean, they will only fight if I'm close range to the enemies, I'm using quadrilla right now).

Now, the dexterity tooltip says: For +1 dexterity, +5 accuracy rating. I see no point in this passive, because it says that the dexterity is passed to the companion, but if they fight close range they will always have no penalty from distance.

My question is: Is there any point on this passive, do companions scale with dexterity for damage? I can't measure it because as mentioned before, companions just fight side by side to me, they do not engage by themselves.

Thanks.