Tiers for clothing (like in DA2)?

[maaaaaaaaap]

Armor and weapons can have tiers, which makes it possible to get better stuff throughout the game.

Is it at all possible to implement this in a mod for DAO/DAA as well?

I tried adding lines to materialrules*.gda only, but that solution did not work (maybe because I didn't create tlk entries for them? I think, however, to do this requires more than adding tiers to clothing in materialrules*.gda, most likely).