That system is great when you have a combo with a turbo or power adder. A even though they've been around for awhile, new tech still is being developed for them and there are gains to be made. In regards to the "best engineering" for the typical naturally aspirated SBC, they've had the snot engineered out of them and gains now are like trying to get water from a stone. Personally, I think the original idea that was floated, giving back 1/2 a hun for each divisional( up to the class index as a maximum) is possibly one of the easiest to implement and track. The question would be when to apply the index. Would it be cumulative after the season ends or after every pair of races you get .01?