I concur with DTH... I haven't seen any varying degree of application with regard to the use of the seat belt sign on CX over the last few years. With the merest hint of light chop, on it goes... along with the accompanying P.A.'s. There are so many occasions when, by the very nature of the offending 'chop', it's almost certainly not going to present any nasty surprises yet still, it seems, CX flicks the switch making for an unnecessarily restless nights sleep. Other reputable airlines on the same route, in the same conditions, don't seem to exercise the same paranoia? I speak from repeated experience too.