My guess as to why the programming can't be change to solve the issue is because you would need to add new code to account for multiple TC gear ratios, rather than just changing parameters. Instead of just going in and changing a number from 2.72 to 4.0, you'd need to add logic loops. The current programming probably is checking the output speed of the TC against engine rpm, transmission gear, and whether the TC is in low range or not. A fix would need to have sensors to know which TC ratio you're in, as well as new lines of code to verify the TC output against the sensor reading. The extra code would require more testing than most manufacturers are willing to put in.