How does "power" work together with Redblade Banner?

So, according to the patch notes:
1 normal enemy = 1 power
1 magic enemy = 2 power
1 rare enemy = 10 power
1 unique enemy = 20 power


So let's say we are using war banner and enduring cry together with war bringer.

The wording on enduring states that you get X endurance charges per 100 nearby enemies.

So, what is the maximum amount of power that I would actually be able to get from a warcry?
Does that mean I would be able to cap my rage instantly?