I dont like to see this kind of mentality creep into aviation."I am doing what I was told to do".Pilots are better than that.ATC will expect and plan around a jet descending at 300,then 250 and then 210/220 in the latter stages.The point though is fly what they tell you.Thats sacrosanct.A company that has its jets descending at 250 or 260 @FL300 will upset the system for everyone else.They may think they're the only ones in the sky but they're not.Some days you'll get slowed up early,others you'll be asked to maintain high speed for as long as possible.Think flexible and always comply.Speed control is a great tool for ATC and denying them that for some pansy-ass reason like SOP's is not pukka.You're a pilot not a monkey.
If the company CI generated a descent of 265,I'd override it to 300 manually based on common-sense and professionalism.ATC compliance,providing its safe for you and your passengers,is a test of your airmanship.I cannot imagine
a pilot saying "unable to comply due SOP" to a controller in the States.He'd get taken out of sequence.They dont have time for such antics.