The output route shape with our without measures should not impact the route geometry.
The problem is the curb approach. If BOTH stop 1 and 4 have SideOfStreet set to Right side and the CurbApproach is set to Right side of Vehicle, then when the route comes to stop 4, to honor the curb approach, it has to go to the end of Lee Street and make a u-turn at F Street.
Change the Stop 4 curb approach to Either side or Left Side and the route will no longer make a u-turn.
Jay Sandhu