I think the key is, small acts of sabotage that could never be considered sabotage, so there isn't any chance of getting caught. Using a hammer that is to small or adding another technology to an already complex technology stack would never be considered sabotage. They likely wouldn't even be considered incompetence, especially in the latter case if the person who added another database/programming language/web toolkit/etc managed to achieve something with in in a short period of time.

Instead that person is a hero, and the costs associated with the decision are initially small and don't show up until that person is long gone.

Repeated a few times the small hits to productivity/quality/etc will result significant lost ground. This is probably even more important long term in the technology industry than it is to a war effort. The sides would have to be close to evenly matched and the war would have to go on a long time for all the little bits of sabotage to add up.