The feat at hand: Conqueror's Heal on Block

Now, normally each character has some sort of feat that is viewed as ultimately powerful, yet countered by another feat. However, one in particular, Conqueror's Heal on Block, needs some sort of tweaking.

Now, the problem is that a player can land 3 lights on a Conqueror, but blocking just one heavy attack heals back all that damage right away. Now, I'm not sure what skill level everyone has, but being able to heal by only blocking every 1 out of 4 hits is not very hard. Normally if it was a gank situation it could be argued that it is reasonable, but the problem is that this feat makes a 1v1 fight basically impossible for whoever fights the Conqueror, and outnumbered fights only add to how powerful his healing ability can be.

The problem could be addressed in a variety of ways:
-Lowering the heal amount to a reasonable level, so the player still needs some sort of skill to stay alive
-Changing it to Heal on Parry, which requires a little bit more skill than simply blocking in a direction
-Change to Heal on Assist, which would reward Conqueror health for saving his teammates (since feats are only active while with 4v4s)
-Etc

I hope this feedback features enough helpful information to aligning a more balanced feat for Conqueror

tl;dr Conqueror's Heal on Block needs adjustment so he is not blindly invincible; some suggestions to help balance it