King Crimson lets the boss see every outcome possible in a situation and he chooses which one benefits him to happen. For example, if someone is about to shoot him, he can choose the outcome where he dodges the bullet and kills the assassin with his stand.
When he makes that choice, the entire sequence of events (dodging the bullet, going behind the assassin's back and killing him) happens at once. In a way, the stand lets you control fate itself.
The reason why people don´t understand King Crimson´s powers is because of the "erase time" line. It's a stupid line because it makes no sense whatsoever. You can´t erase time.
The Bruno switching was just a cool visual that is never explained and it never happens again.