User blog comment:Snes/A Rework of the CDR System/@comment-69.141.8.150-20120619164931/@comment-4900160-20120619173555

Armor and MR have no decreasing returns at all. Saying this proves you do not understand the way it's calcualted? The only thing that matters is "Is it worth it to buy more armor or more health". Basically, the more health you have, the more armor becomes valuable, and vice-versa.

Stacking resistances would actually be a great idea in most cases if there were no LW or VS, since these items nearly divide the usefulness of your resistances by two.