Best post yet by anyone on this topic. Well Done, Sir!
The only thing that really confuses me is the reference in the 139 RFM (if as it is described to be) where it references "IFR" rather than "IMC".
As it describes it now, if one were operating at an Airport with weather barely less than VFR (say ceiling 900 feet and Vis .9 Miles) thus making the control zone IFR one would not be able to depart. Or do I miss some exception or waiver or loop hole in the Rules?