I was watching a video yesterday (not about marking). There were quick scenes on various things. One of the opening scenes showed a lady marking a stencil with a blackboard eraser ... she just rubbed it over the fabric ... which was very quick. Unfortunately, I don't know if she was using chalk or some sort of powder. Would anyone know about this?
FMQ with a stencil would still be a slower process but the marking at least would be faster.