A problem with FTLs is that they assume human beings are machines that can be switched OFF and ON as required during rostered rest periods. That's obviously not the case and I personally find it very difficult to get enough rest during the day before an overnight flight. Circadian rhythms make it difficult for many pilots to sleep properly during the day; at home there's the pressure of family life, while down route we have the problem of cheap, noisy crew hotels. Complaints to management don't get very far.
That said, I don't have a problem with the regulator granting temporary variations, provided suitable safeguards are in place (eg adequate notice to the crew, etc). I do find some of the provisions of the FTLs a bit ludicrous, however. An overnight flight with one sector from MEL-HKG requires 3 crew, but an overnight pattern with two sectors from HKG-DPS vv and a longer duty period doesn't. Which one is more fatiguing?