live tuning is basically real time. Say you want less smoke from 0-25% throttle position, you can make that change and physically see the change in smoke out put while on the dyno or street, not possible on a 6.0 or 6.4. Hopefully that helps. Duramax and cummins guys typically tune off logs, always did with my s4's, and my brothers duramax. You can basically do the same thing with a 6.0 if the equipement is there. Eric has been able to make some good advancements by reading graphs and tuning on the dyno. Thats why theyre such great tools, not just numbers.