I personally highlighted that the fixation with acclimatisation shows how disconnected with reality the experts behind FTLs must have been. It's not uncommon to do 3 day trips with 24 hours off then 2 days off then rinse and repeat. It's shift work and in this case time zones have little to do with it. Every 24 hours rest is a reversal and 24 hours rest simply does not work with the human body to rest properly twice. Then on 2 days off you are not only meant to have magically recovered the lost nights sleep, but expected to then reverse back to days ready for the next. Do this 5 times a month and what do you expect.
A lot of research recognises that body clock reversal takes serious time. It's always been taught that with fatigue you can't restore missing sleep without getting it back somewhere properly - not an hour here and there on a seat, not an hour in an aeroplane bunk board, in a bed. Bodies aren't machine's that's why shifts generally work in patterns or runs. reversing the body each time you do a shift is about the most destructive thing you can do rest wise. Compound this with time off that is not fit to adjust and you have boil in a bag burn out.
In these enlightened times we also recognise that being sentient creatures humans relations and time outside of work have a huge impact on fatigue and stress levels. So I think the FTLs need to account for this rather than viewing rest/days off as a marathon of odd sleep patterns.
The times reader - I think your last remark was spot on the money