Thanks for the copy paste from internet, could have thrown quotes up,
https://www.quora.com/How-can-exhaus...ngine-knocking
Utilizing EGT in place of a knock sensor is a no no, EGT's are far too slow to respond. By the time your EGT rises(sensed from sensor), without knock control, you motor will likely have already suffered. Even with knock control, on most stock cast pistons for example, you can get toasted quickly. Forged bottom end you have some headroom with knock typically. Just saying, neither is an end-all solution.
EGT is a tuning aid in combination with knock sensing for a most reliable application. Sure EGT can be used, but dont act like its a "replacement" for knock control or you can tune around that.
The point is, if you want a reliable in all scenario's application, knock is important. It just proves a standalone is not for everyone which does not provide knock control. Im a firm believer FT product is racer focused(their marketing as such at the end of the day), and not for the average joe. But hey, we all get stuck low on fuel, what if you cant get that 93? What if you get some old 89 gas? People want to go out and enjoy their PWC, not have to pull out a laptop, or have to have multiple maps etc. Can this be done, sure......Just saying from perspective, most people want to set it and forget it.