As you say back to Andrew's thread now.
Just one last diversion if I may....
I only have so much detailed info from working 50odd years in chemical labs where the making of the tea was a critical operation
Critical as in - everyone knows the world stops unless lubricated with sufficient cups of tea? Or critical as in, you were actually blending/refining teas?
Curious minds....
Andrew: Presumably, the low end of the resistor was providing the maximum temperature (i.e. tending to zero ohms). With your old pot failing "high resistance", it could no longer tell the machine to go to maximum temperature. Normally if a pot fails at high resistance the issue is with the wiper; often the wiper & "output leg" are wired together, which I assume was the case in, er, this case.
So... that given... it wouldn't matter if it was a 28k pot, a 50k pot or even a 147k pot... the low resistance end would give the maximum temperature.
However... I'm sure you've thought of all that stuff (cos I knows you are good with electrickery), so if I'm talking out of my Chinese hat, just say so...