Mercenary Attack Rating
I've read online that mercs in D2 have an AR, even though we can't see it. My question is: Can I put diamonds into their armor and helm to raise it, or can it not be changed?
What I have managed to find is a table of stats, and a "calculator" tool.
There is nothing specific about the effect of Diamonds on the Hireling's AR, but the Tool does have this subnote stating that stats can be affected by gear (emphasis mine):
Note that resistances are capped at 75 unless the hireling wears something that increases max resistances. For that purpose, the calculator will show the value before the cap.
It does state resistances, but I don't know if that does mean it can affect AR as well.