But you missed one crucial thing, what is happening right now, is not seasonal testing. This is a major complete overhaul of the entire attraction. One of the important parts of the sandblasting process was not only to remove the paint, but to remove small areas where corrosion will have built up. 30 year old steel will have corrosion, usually small if the paint job was good, but it usually always has it in metal this age. This happens even in areas where the paint application was good, even more so in areas that have been scratched or damaged. This cannot be done with paint on. This type of work is not testing for cracks, fatigue, but removing corrosion.
When work this extensive is being carried out on Nemesis, there is no choice in the matter, the train chassis, (if they were refurbished) and existing track all have to be sandblasted and repainted, it is not a choice, it is a requirement. If the company carrying out the work believed they had a choice, they would soon be removed of their qualifications and permits to allow them to do this type of work. As the work done will be inspected and signed off by an independent body, exactly for this reason. Chances are not taken, specifically when this machine will be used primarily by the public.