increase to 3 iterations, and limit statistics used in drawing the validation LH parabola plots to be 100k (instead of all), because that this validation takes to long time...
change back to use full statistics to draw the LH parabola plots, because the LH minmum is really fitted from the full statistics and it is an average, only first 100k events cannot get the right coverage., For saving fitting time, only do this plots with debug>1 .