A simple proposal here: Fire once, check if the spark plugs are ok, prepare the experimental set up again, and fire again. Repeat.
I’ve been following LPPX twitter and it seems that shots are done just once every week, on average, because the spark plugs are too fragile. Since this stage of research is about exploring the feasibility of the technique, I guess fast repeatability should not be of concern right now. Taking the september 30th video, it seems that there was a shot every few seconds or so, maybe this is too much stress on the system. I guess there shouldn’t be this kind of thing and instead be cautious like in the suggestion. Maybe the number of shots per week would be much higher.