That is exactly what you should NOT do. At best, you can use a HP stock repository file to COMPARE to a file you currently are using. You cannot take a repository file and flash it to your current computer and expect it to work.
Even using a stock file for a COMPARISON may not catch all changes. For instance, if a diablo was used and changed a parameter that is not defined within HP you will never know it was changed when comparing within HP. If you want a truly fresh start and stock OEM tune file on GEN4 and newer platforms, you have to use GM SPS/TLC to flash a stock tune.