The basic question, does being behind an obstacle prevent a survivor from being a threat?
Relevant glossary entries I've found:
Threat: A threat is any survivor that is not knocked down or using special gear, terrain, or abilities to prevent being considered a threat.
Obstacle: A terrain rule. This terrain blocks survivor and monster field of view, interrupting ranged weapon attacks and monster targeting. ...
The wording is a little vague. We know just being outside of the Field of View does not automatically negate threat, but the glossary entries are ambiguous. When the Obstacle entry speaks of "monster targeting", is it referring to targeting in general or specifically "in view" targeting? Likewise, when the Threat entry refers to "terrain", is that only terrain like Tall Grass with special text, or does it include more general terrain traits, such as "Obstacle".
I have a bad feeling we played our Butcher fight incorrectly... again!