There was great mirth enjoyed, a few years ago, when the highly experienced captain of a charter airline was operating his a/c on a schedule route on behalf of the parent 'major'. It was only a short hop, wintery morning, busy major airport XXXX with lots of likely delays in handling due to the conditions and congestion etc. He was on the 1st of a multi-rotation day.
He deemed it prudent, considering all things, to tanker round trip fuel + some for Holding at XXXX . (It could be done without risking wing icing during turnround.) However, the parent 'major' did not tanker fuel on that sector and quite a contest enschewed between captain & dispatcher. In the end, as long as the captain annotated the fuel order with the reason, all would be accepted and the dispatcher had covered his rear end.
It took them a while to de-code. ME as the reaon for the extra fuel.
In the end, as Hollywood would have it, he went in and out of the congested hub with no delay, while other a/c sat around waiting for fuel. Carriers that had tankered in had burnt holding fuel at XXX, and those that handn't tankered needed some anyway, thus overloading the fuellers in the early inclement morning.
Another carrier, very long-haul charter Europe to Caribbean had min plog policy, and again requiring justificatioon why extra was taken. The argument was that cont' of 2500kgs gave you 40 mins anyway. As we were operating at the range of the a/c, across the N.Atlantic with jet streams of upto 150kts headwind, into airfields of very limited approach aids and parking areas, the likelyhood of delays, inbound was high. A diversion was a commercial nightmare. Fuel always seemd the cheapest insurance, but in any case, it was often not possible to carry any. We were nearly always at MTOW, anyway, but when not, the idea of leaving 2000kgs at home when setting off on a 13hour sector across the pond, struck me as a stress causing exercise. Sadly, the C.P. still wanted to know precisely why you'd made your decision.
It grated that you could have years of proven experience, the company was happy for you to take 200.000.000U$ worth of machinery and all the pax halfway across the world, but they were worried you would keep all the Green Shield stamps for yourself.
I would accept that on the return leg, with tailwinds & a wealth of diversion airfields available, & CAT 2 at home base, the attitude should be different.
Experience and thoughtfullness will often prove successful in avoiding the poo. I just wish it was encouraged more, rather than the 'belive the computer' attitude and don't think too much. And if you do question the 'oracle' of microsoft, woebetied unless you have a cast iron explanation. I find that attitude from on high to not be the best promoter of safety. Perhaps a revisit to the story of BY at GRO might awaken some thinking.