looks like the goal of your system is to make it so that events like a long ass fight don't hold up the entire RP. The problem with this system is that it requires the players to know exactly how long an event is going to take, what is going to happen during the event, etc. I'll use your time stamp example.

Character A and character B are fighting. A thinks it's going to be a sizable brawl, so he writes that wen the event ends, the bar is going to be a mess. But then Player B goes down in a single punch, or maybe B simply retreats outside instead of sticking around to fight. Player C would be misinformed and subsequent players would walk into an area that shows evidence of a bar brawl where a bar brawl never happened. And if the bar brawl did happen, it's still a nightmare for player C to enter the area because they don't know what exactly happened. They might spend several posts trying to retrace the events of the fight, only to realize that character B was knocked out by the doorway and probably would have been spotted much sooner. 

If players want to create an isolated event, they can collab it. This keeps the event inside a single post and lets everyone know what happened. If people insist on having brawls in important locations. Find a way to bring the important event to the players. Character D might need to see an informant in the bar. Character A and B's fighting scared the informant into running outside. And so now, character D can run into the fleeing informant. Now D's story can progress while the bar brawl continues.