For the purposes of this exercise, yes, that would be an automatic "yes." The whole point, after all, is to think about how this would impact the game. The GM says yes, but still has to make it coherent. The consequences of "always yes" are the interesting part.
This is interesting. I never even considered that the players wouldn't know that this was the case. But now that you mention it, the players not know would inevitably result in a different game than if they were aware of their "power". I think the former case would end up resembling a "normal" game much more closely than the latter.