Both, I'd think.

But I've never played a giant sword spec. I've heard parry is strength based though.

I think ward of blades gives you a second chance to parry, so the whole not good for people who parry well is open to interpretation.
The idea is that if you parry well already, you don't need it so you'll get more milage out of another legacy.

In my short sighted mind, ward sounds great for a character that parries well already. Ultimate master of parry.