Had I done so, I might have known sooner that a heater relay on the circuit board of my spa was sticking.
The past few months I've not used my spa very much, and as luck would have it, when I did everything seemed fine. Then a few days ago I happened to check it and the temp was clear up to 105.
The heater relay would evidently stick and run the temp up until the safety kicked it off, then it wouldn't kick on again until my thermostat setting (100 degrees) called for it.
So, I just had the circuit board replaced Thursday, and will be watching my meter to see if that puts an end to it, though the spa dealer & I both agree it seems out of line to think it could be the complete problem, as the spa is well insulated, in an enclosed patio room, and normally only costs about $15 a month to operate.
Still doing some other checking around, but hopefully that was the problem. Thanx for the inquiry, Scott.