Um, no. They took 5 different systems and added them together. They simply gave slightly more weight to DRS and RED than the others. The formula is right there in front of you. If they added them all together without the weighting, it would look like this: 20% TZ + 20% DRS + 20% RED + 20% UZR + 20% DRA I think the percentages might be throwing you off. The percentages do not indicate "blending" it's actually "weighting." A blend would not count the same events multiple times, the algorithm would account for that with a "blend." And none of this changes my point. Most of these systems count the same events. By adding them together, whether you choose to emphasize a couple of the systems or not, the result can only be obtuse and in the case of SDI, grotesque. SDI creates the opposite of a bell curve for players that are good or bad at whichever traits are counted the most in the 5 systems. As for stumbling around in the dark, everyone knows why SDI was created and it was not to create a new defensive algorithm to supplant the others. Considering "the dark" is five other systems that they borrow from, there's not much need to flip on the light.