Originally Posted by LeeG

straight/flat bars are good for descending on steep dirt where you can slide your weight back and have control of the brake levers. Beyond that, IMHO they are abominable WITHOUT bar ends or bar extensions.

A simple thought experiment, you're sitting on your bike and you put your hands on straight/flat bars where your hands are ROTATED thumb inwards. Try rotating them further, can't do it, your forearm is at it's max rotation. Ok, rotate your hands so rotated all the way out with palms up and thumb outwards. Makes no sense does it? Can't grip the bars from underneath. Ok, now rotate your hands to neutral with thumb pointing forward or slightly inward as though you were about to shake someones hand. Now look back to simple one speed bicycles from 50yrs ago, the bars sweep back so your grip is neutral. You can get that grip on the tops of drop bars at the bend and on the hoods. You can get that grip on extensions added to straight bars. You can get that grip on traditional swept back 3spd bars. You can get that grip on the extensions of flat bars but you cannot get it stuck on the grips of straight/flat bars.