The software plays an important part in the overall performance of a vehicle, but it's not the only criteria. What is most important is to properly match the "map" used for the modifications you're made to the vehicle. Using a map designed for another set of hardware will NOT improve performance and it is quite possible that doing so can actual cause engine damage
This quote is taken from Cobb's website as well and is an answer to one of the first FAQs "What is a map"? We could all easily fall into a he said/she said and start dissecting Cobb's instructions like Supreme Court Justices but...