Split heat pump piping design

[NoNickName]

In heating mode, would it be fair to say, that if the air entering the coil, is closer to set point, then the actual amount of energy required to keep the building warm is less

No. The on-coil temp is after the air-air recovery section. It's all-fresh air, therefore independent from the building temperature. The on-coil temp is proportional to building temp only at fixed ambient air temp.

Does this make sense NNN?

If Fujitsu and Daikin do so, then it must make sense. I'll think about it. I'm not sure whether Fuji e Dai make all-fresh air handlers, though.
Thanks.