It would be a simple understanding of their mechanics, nothing advanced. The most he would know about demolitions is how to shape charges, plant on walls/doors and blow them for an entrance.  Additionally, all military personnel have a basic understanding of field medical care, such as a quick patch up or assisting the main medical personnel if needed.  

The only thing he specializes in is special operations-type warfare; such as unconventional, direct action, special reconnaissance, and supporting main force engagements. In a short-word, he's your spec ops go-to guy when you need shit done without the political backlash of a main force.