Ran into a situation last night where a character had access to free triggered ability (Hyperawareness, spend 1 resource for +1 to either Intellect or Agility). They also had several resource available to them. The question came up as to whether they could spend multiple resources to get multiple bonuses on the same skill test.
Took a quick look whether they could trigger that effect multiple times on one test, didn't spot anything at the time so went with The Grim Rule and only did it once. And this does feel like the correct way to treat it. But I'm going back over the rules again this morning and still struggling to figure out whether these abilities are once-per-opportunity, or if you can repeat as long as you can pay the cost.
Will continue running with the once-per-opportunity for now, but would be good to have a confirmation from somewhere within the rules!