That's funny. We used this exact protocol on occasion growing up to ensure a fair fight.
That was some sort of mark of respect.
No one jumps in and it is a clean fight.
If you get whooped you get whooped,
the friends keep it from going too far
and then you shake hands (I guess sort of optional) and everyone goes their separate ways.
If all above is honored everyone leaves with respect including the person who lost the fight. And shit is squashed.
Decent system imo and probably been around for Hundreds of years or longer