Plumbing a fuel system

I looked at the Pro Systems diagram as well. NB Turk is explaining that the bypass should come after the regulator is fed. Say at the end of the line, so to speak. There are diagrams that bypass before the regulator, yet that seems to defeat the objective.

Just "my" understanding of the system function.
The regulator is after the carb and the by pass leaves the regulator and returns to the fuel tank