John Rumm pretended :
It needs a little bit of experimentation to set the profile the first time -
basically waiting for colder days and seeing if the system still heats the
place comfortably and quickly enough. If it doesn't, then you just tweak it
up to a steeper curve. It also helps if you have appropriate rad sizes for
the rooms, and the system is balanced.

Balanced?

I have always assumed there was no need to balance a system, where
TRV's are installed.