Unless they added some 'secret' penalty for using heavy, it's still the best set to use defensively, as that's the only reason you'd wear anything over Robes outside of min/max XP (which would be your offensive set/glass cannon build).
The way the Con changes work for your HP/CP, the extra HP on the mastery never meant much to begin with, and the set bonuses and OE bonuses on heavy are still better overall. Even more so after the update (passive debuff reflect chance on +8 laaaaaaaaaawl).
The only way LA might be more interesting is if the mastery skill enchant scaled in some crazy way with the base value. No all this update did was make wearing LA less terrible and made Robes a much better alt set. Which makes all the people knee-jerk selling/trading their expensive as ** heavy armour even funnier...