1impulses are not meant to be controlled otherwise they would not be impulses 2the given time is for investigating and developing novelties and innovative ideas unlike the bullet format where people play pre meditated ideas or pre memorised moves and seldom have any new novelties or innovative ideas over the board thereby improving your skill to innovate over the borad in over the board situations.
Why do so many players play longer time controls and use little of that time?
When a game is starting most players can just blitz it out. Why think on an opening you know and like if you can go for it?
Then you get to the middle game and because people get used to playing blitz, and bullet. If you play a lot of bullet 15 minutes is a lot of time.
Many people have poor time management skills.
I like to think while using my opponents time too. If we are playing chess and you just thought for 2 minutes on 1 move then I get to use that time to think too, and I should not really need to use all that time.
Also, only about 20-30% of chess positions would it be of significant benefit to be thinking longer than just a short time.
Then lastly you get blowout games. Do I REALLY need to think very long if you have hung a piece for nothing?
I literally memorize the common variations of the opening because the amount of games I do so I know the next response to my opponents moves, but if it is uncommon then I will think around 5 minutes calculating variations to do the best move/