Tremors/Aftershocks Don't Work with Falling Thunder?

Unsure if this is a bug or not, but it doesn't appear that the Aftershocks triggered by Tremors support interact with the Power Charge consumption portion of Falling Thunder at all. The aftershocks neither inherit the charge consumption modifiers of the initial skill use or consume new power charges for their own modifiers when triggered.

Maybe this is intended functionality, but I figured I'd mention it anyways.

+1 interaction either needs clarification or is a bug