STOP PRESS
I contacted these peeps
and pressed them on the Q of a thermostatic mixer, and the (potential) problem of the mixer throttling the hot feed and exacerbating an output-too-hot problem.
Reply:
So things are indeed moving on. Redring need to up their game.
I contacted these peeps
and pressed them on the Q of a thermostatic mixer, and the (potential) problem of the mixer throttling the hot feed and exacerbating an output-too-hot problem.
Reply:
Yes it is ok, the water heater is electronically controlled which adjusts the element power according to flow rate and temperature rise through the water heater.
So things are indeed moving on. Redring need to up their game.