Originally Posted by CZAMFlyer

It's not that we've "never sped" or done some other seemingly minor transgression. But I can guarantee you that if you said to a cop that pulls you over: "everyone else does it...what's the point...live a little" it will get you exactly nowhere.

It was an unfortunate analogy used there. Many police will tolerate drivers going 5, 10, even 20 over the posted limit with varying amounts of discretion. But if one day they decide to enforce the speed limit even after years of turning a blind eye, is it useful to object and make excuses as to why you should be exempt from that limit and list a number of reasons why driving faster should apply to you, and hey, may as well point the finger at the cops for loose enforcement beforehand!

So go ahead, take whatever you deem suitable on your next flight. But if you exceed the limit for any reason, prepare for the possibility of paying extra and for any airtight rationale to make little or no difference to the airline.