How do MCS design temperatures relate to the Passiv Smart Thermostat?

The MCS design temperature calculations aim to ensure that the heat pump and crucially the radiators are sized correctly to heat the house sufficiently, even in cold weather. However, there is no requirement for heat pumps to be limited to operate at only the design flow temperatures.

"MCS requires weather compensation to be available on all space heating systems but does
not stipulate how this must be set up." - MCS Domestic Heat Pumps - A Best Practice Guide

The Passiv Smart Thermostat removes the need to set a weather compensation curve or flow temperature settings. Instead, it learns how a home heats up and cools down and continuously optimises the heat pump’s flow temperature to maximise its COP. Weather compensation is applied automatically, incorporating detailed weather forecasts when an internet connection is available.