I'd just like to know how they make sure it's working properly for each game? Has there ever been a game where it's broken down or has given a blatant wrong decision? Things like this don't get questioned when they really should. With VAR coming in next season look at the rigmarole it's caused and yet goal line technology isn't questioned?
The only way to question it is it's not working properly and it's not about the thickness of the paint/line as somebody said, the measure is really the diameter of the goal post (based on the (virtual) camera view) which is standard (I guess). So I am not sure what you are up to.
They must test the goal line technology before the game, to check camera positions and calibration etc?
Hawk-Rye tracks the balls position, so I do not think it compares it to the goal line, so the thickness of goal line paint etc would not affect the balls position.
We have had goal line technology for 5 years and I don't think anyone has challenged any of it's decisions, so compared to how it used to be, it is much better.