You don't have to do it for every call. Measurement calls would be easy to do with sensors. Tennis for a long time just had a sensor on the net to detect 'lets'. They still used line judges though for out/in calls. Football could easily implement technology for first down, goal line and out of bounds calls.Going to have to put sensors in the pads then too so you know when their knee is down. Or just have pressure sensors on the field to be able to see every foot or knee or hand right as it touches the turf. Or better yet, let's just turn football into eSports and just have them play Madden instead.
