Yep, only ever tried it prior to TOD (otherwise why bother). To clarify, the thrust/drag required stuff happens shortly after transition. Can’t see how it’s mandatory for VNAV approach, you have actual QNH set.
It may be cultural at our company, as some people enter the QNH but I’ve never seen anyone enter the temp so when guys/girls insist on setting/Changing QNH in FMC I ask why they don’t enter the temperature as well?