Originally Posted by pmsherman
The disttribution of power is controlled by the design of the buss bars that the breakers plug in to. Most breaker boxes are designed with adjacent breakers connected to different legs of the power line which facilitates installing a double breaker for a 220V appliance. RV boxes may not be designed this way to decrease costs.
OK Phil, you had me curious. It appears that we are both correct. From what I have been able to see/read from the WFCO, Progressive Dynamics, and Parralax sites is that the horizontal 50 amp distribution panels (with a dual 50 amp breaker in the center) are indeed setup with the left side being L1 out from the center of the main 50 amp breaker(s) and the right side is a separate L2.
As you stated, this is for cost savings and dual purposes. These 50 amp panels can be also be used as 30 amp panels, which then only the left L1 side is used as per this from WFCO.
I can't find as something as near detailed from Progressive Dynamics or Parallax but will keep searching. This was interesting and I learned something, and may can help members with it.