target, I know you're having a bit of laugh, but you bring up an interesting point: If a thermocouple fails, does is actually affect the engine operation?
I know some military engines where the thermocouples are part of the control loop (as in controlling the variable exhaust nozzle on an afterburner), but I can't think of a single commercial engine with such a feature. In fact I was told the airlines' engineering depts. would not accept such a system; the thermocouples are for readout only.
Enlighten, please!