Since I am uneducated, and you're the educated SME; I will look into purchasing tunes from you. Because of all of your first hand experience in the field.
Oh you don't sell tunes? Perhaps its best to leave the methodology to those that do. If one requires data logging file be sent back and the customer understands and is willing then so be it. If another tuner does jot require logs sent back, and the customer understands then so be it.