So especially when riding a TT close to FTP/LT2 it will be a balancing act depending on your physiology and if overall your condition and resulting time suffers more when riding unevenly (NP to AvgP higher) than you gain by riding stronger into headwind.
In this scenario I guess it’s just a couple of watts difference and depends how fast you recover from work above threshold. Seems like it’s ~threshold into headwind and just below threshold with tailwind. (The cited example makes a point for the overall time calculation but at the same time is a bit confusing or misleading as with ~80min 225watt (maybe just below FTP) you can’t just go 250 half the way…it will cook you.)
As duration grows it seems that NP to AvgP ratio could grow more.