Why is it that when you have a gun that has a scope when you shoot you loose your scope. then you have to hit youe scope key again to get you scope back?
It has be a pet peve for me ever since Halo Combat Evolved? You would have thought by now they would have fixed it by now!! Geeze Louise!!
Peace! 
Is this a joke thread?
Actually as someone who has played Halo for over a decade now, I agree with OP, de-scope is honestly a bad feature and if nothing more should have a toggle for people who don’t want if not outright remove it. Flinching is fine, de-scope is not.
Because, at the time, you were using the helmet’s integrated binoculars. Not a scope. It makes perfect sense you would descope when you shot a gun that doesn’t have a scope.
Descope is an important balancing mechanism for most of the games. Halo 4 doesn’t have it and it’s noticeable in matchmaking, resulting in dragged out fights at extreme ranges.