Usualy, as OL i use my Threat tokens to increase speed and attak of my monster, like the heroes use their fatigue to do the same. But probably i miss a step, because the manual allow this kind of action in the outside encounters, but i always use this rule in the dungeons level too.
i search in the Faq if somebody ask the same things but nothing. But i found strange this skill is limited in to the outside encounters.