I don't necessarily think spidey senses are required for that determination of likelihood of concealment.
And if the gun jams, that is a potential consequence of choosing a warning shot, which also must be factored into the equation. Generally, a warning shot shouldn't even be considered unless someone is fairly certain a warning shot alone will help them achieve the goal that they desire. i.e. it shouldn't be used in situations where one reasonably expects that the warning shot will not instantly gain the desired response (i.e. the threat runs like hell).