They are talking commercial, and you are right and forgot to add if you fit the TRV with the head horizontally you will negate the convention current up the pipe, another alternative is to use a remote capillary, but all this costly and messy, and they can get damage easily, commercially we tend to have a single zone valve controlled by a BMS and a room sensor, usually with a 3 Deg C adjust band 1.5 up and 1.5 down from agreed set points.
Owning and operating commercial HVAC system is expensive and maintenance must be taken into consideration too, in a school there is now a tenancy not to install radiators with TRV, they get damaged and messed with, UFH is pride of place no one can fiddle and even quality bespoke dwellings do use radiators.
I have designed 6 bespoke house in the past 10 years and not one radiator anywhere, the spec building will take some time to catch up but I think they will.
We have in recent years seen power sockets lift up higher, you could put the rad valve TBOE so people don't need to bend down, I have electronic rad valves on my system, don't need to bend down, once they are set you never need to adjust them again, extremely accurate temp control, they even make wireless TRV and the World moves on, as for 2% extra output using TBOE we will need the tweak the ABV or use the next size boiler up one. :bigcry:
Tony