As SLF in the past few years on BA in world traveller, world traveller plus, club Europe and club world, I've never had occasions where the CC were other than at least 'Correct'. That was two occasions out of well over 150 flights in 3 years. The rest of the time, they were excellent
Unlike other airlines - America West, Air France and SAS who were universally pretty awful.
But I speak only as I find, and it's easy for others to have had crap treatment on a flight where I didn't. BA do seem pretty bad on having diet tonic in economy and WT+ on long haul, though!
I guess it comes down to the fact that any cabin crew can be pi**ed off given certain circumstances, and this then reflects on how they treat the slf.
American, however, seem to have permanently pi**ed off cabin crew - and so the slf (even in business class) pay the penalty!