Ex-LOML D. would drive me insane by acting upon his sincere and well-intentioned belief that it takes 5 (or at most 8) minutes to get from any given point in NYC (not just Manhattan - NYC) to another.
I realize now that I am exactly the same way. Worse, (1) I'm only fully realizing it after years of torturing friends with my lateness, and (2) I actually believe that if a destination is within oh say 10 blocks of my apartment, it will take me ZERO minutes to get there.
I apologize and vow to actively use my brain to calculate actual probable travel time (rather than assuming it is "null set"), and will even pad it to ensure timely arrival.