This is a big stretch (but it was bothering me so i posted it anyway =P), but in the latest beta patch they made it so you can smith light imperial armor. Honestly i never even noticed i could before because there is always plenty of it around. I wonder why they would fix this over being able to improve other glitched armors and weapons.

I wonder if the next DLC has anything to do with the imperials... I dont recall anyone ever asking to make light imperial armor.

A really, really big stretch at that.

I doubt it.

Only the Studded Imperial Armor was non smithable.

Wasn't it so that you couldn't make light imperial armor, but tempering it was possible, with the exception of studded? That is how I remember it anyway.