[Rune] Buffeting Gale

Hi! Rune isn't an OGL game, but I thought this would be the most appropriate section for this post. Moderators, please feel free to move this post elsewhere if necessary.

I've been getting the itch to introduce my local game store crowd to the joys of Rune. I am rereading the rule book and noting problem areas or questions that I have. I know the game is old, but perhaps there is some advice to be found hereabouts.

My first issue is with the divine gift Buffeting Gale. I remember from playing years ago that even with the errata Buffeting Gale seemed overpowering. But the wording is a little confusing, and may have led to some of its extensive use.

Specifically, the errata says that "duration of this power is X rounds." I'm not sure what a duration for this gift means. Without the errata it seems like Buffeting Gale works on each and every successful melee strike you make in combat. But the gift's description includes the line "you can choose not to use this power on any given blow your hero strikes during its duration." This implies that you activate the power, it lasts 1–4 rounds (based on your level in the gift), and then it stops working.

How often can you activate it? Once per encounter? Once per combat? Once per session? Once each time you buy it? (In my Book of Iron Law, I would probably set it to once per encounter, but I want to know if there are any other insights here.)