I too am a little confused here. I always end up using extra amps, for fills, or just extras, or anything really and have never subscribed to the run amps gain fully clockwise 'rule' some have. The systems driving the amps always have bags of spare. Using parallel splits just means to restore the status quo - you just turn everything up a bit, or in my case, shove the master a bit higher. The split loss is easily made up as nobody ever goes anywhere near digital maximum - as there's no need. In fairness, I don;t need to use the old splitter box very much as the stage boxes now have so many outputs - you just patch a few extras in. I've never noticed any difference in practice using the splitters, or extra outputs.