You are tuning a customer’s car, you are on a tight deadline, or you are unwilling to spend hours reading forum threads when something goes wrong.
This is what serious LS1 enthusiasts mean today. These devices (like the HP Tuners MPVI or EFILive Flashscan) connect your laptop to the car. They don't just upload a file; they allow you to edit the raw code of the PCM. ls1 flash tool
The LS1 Flash Tool: Bridging the Gap Between Hardware and Performance You are tuning a customer’s car, you are
: Includes features to force a PCM into recovery mode if a flash attempt fails, preventing "bricking" of the unit. You are tuning a customer’s car