Yes, I agree with you all. A defective TSOP flash is evident immediately. If the Xbox works right after the TSOP flash, then the flash was good. If something goes wrong days or weeks later, then they were mucking around with it.
The problem arises from the customization of the BIOS with personal preferences to alter the flubber animation, or to make the Xbox logo red, or something like that. If you don't do it properly, then you can end up with a $150 paper weight.
A bit off topic,... but I had one guy who wanted the TSOP flashed, and he told me that the Xbox suddenly stopped working; it kept rebooting repeatedly. He *swore* to me that he didn't do any modifications with it. He first gave me only the Xbox and a bigger HD, but not the original stock HD. When I asked him more about the repeated rebooting, it sounded very much like the infinit clock loop, but he swore that he didn't muck with the Xbox. I told him that I will need the original stock HD anyway, because of the locking code. When I unlocked the HD and looked inside, there was the familiar Phoenix file and the font exploit. The Xbox was in the infinit clock loop, after the black out due to the thunder storm. After I flashed the TSOP and revived his Xbox, I called him up to confront him, but he has no idea how the Phoenix file got there. He has no roommates, only a dog. He made a joke that the dog may have been screwing around with the Xbox. What's surprising is that even with an irrefutable solid evidence, they will continue to deny everything. Is it because of embarrassment, pride, guilt, or what? Since this guy is paying me for a service, who cares?! Am I naive for trying to find logic in human nature?