Lowering the N overall reduces surge growth. I know in the UK, they do not fertilize with high rates of N for green either. Green comes from iron. Their fall application tends to have a high rate of iron. I would imagine putting down more iron and less N for the last application might help with surge growth, while still keeping it green. I use higher rates of micronutrients later in the year for a different reason. When the temperature cools, grass has trouble picking up micronutrients from the soil and turns chlorotic. High rates of N will either fail to do anything or give me surge growth that is still yellow.