I have personally fixed tuners mistakes myself. I been tuning car's since they were tuned with a flat screwdriver. There is many ways of tuning fuel on modern vehicles and each tuner has his way. Most of them just tune your wot and then just touch the other areas a bit. Because it would take about 16 + hours to tune a car perfectly on every possible scenario. Must tuners learn from mistakes and it takes a man to admit it. But vent buddy is your thread and I hear you bro, it sucks to pay for someone else mistakes.