Indeed when there are large outages is when utilities often find out that the models Don’t quite match reality. One example would be when 1200 MW of generation

Indeed when there are large outages is when utilities often find out that the models Don’t quite match reality. One example would be when 1200 MW of generation tripped in the WECC region and they found the effective droop of the system was about 8% instead of 5, and have since mandated that every generator over 10 Mva is tested every 5 years to ensure the equipment still matches the model.