Something that came up in a recent game;

Should a character using a savaging action from a grapple be able to activate a simple charm for use in that attack?

Some of the simple Solar Brawl charms specify that they interact with grapple mechanics, but none of them directly state that they can be used in place of a savage (or other) grapple action- it is sort of just implicit.

Specific example; using Hammer on Iron during a grapple to deliver a flurry against defence 0.

Clarification would be much appreciated.