Courage of the Colossus is too hard to trade against as a Melee Top Laner

I think it's a fine mastery for teamfights, but I feel it outclasses Grasp of the Undying (which itself isn't much better than Greenfather's Gift) as the best laning keystone as well as the best teamfighting keystone. It's just awfully hard to trade against a shield like that.

It also beats Bond of Stone, where the impact feels kind of invisible. It also has less downsides than Bond of Stone (30 second cooldown for massive shield vs taking more damage for your ally)

Can we make this change to reward taking it for teamfights (which is where tanks should shine) over lane pressure?

Cooldown: 45-20 (based on how many enemies were nearby when the CC was applied)