Answered +/- Light Radius gear on hirelings?

I am tempted to put a

Darksight Helm on a mercenary (not the best option, but it is one of the few ways to get Cannot Be Frozen on a merc, short a

Cham rune), but I fear that the -4 to light radius will effectively blind her.

Does +/- light radius gear have any effect on hirelings in the first place? If it does, does it change their behavior?

I've been googling for 20 minutes and I cannot find an answer to this question.

Thanks for the info! I appreciate the reply.