Normal clothing can offer faster movement and ocassionally some nice stat bonuses (+1 Charisma, endurance or agility. I don't know about you, but an enemy crit is one of the most dangerous obstacles for me well worth losing the extra DT just to avoid those. With perks, light armor lets your character move faster and crit more often PLUS decreases the likelihood that an enemy crits you. Seriously, is there a point to any other armor besides Light Armor?