UNCTAD World Investment Report 2012: Proposing Special and Differential Treatment in Investment

See the recently released UNCTAD World Investment Report 2012.  It proposes S&D treatment in investment, including provisions for non-binding national treatment and "fair and equitable treatment" norms for the less developed party.  I wonder whether they have determined that these types of reduced commitments would make up in policy space for development what they must lose by marginally deterring investment.  In fact, I wonder whether they have determined that national treatment and fair and equitable treatment actually constrain policy space for development.  Anyone have a case in which they think there was such constraint?  I don't find the "regulatory chill" arguments to the effect that states don't legislate for development because they fear suits based on these norms appealing--largely because in the absence of a smoking gun case any such effect seems to me to be largely an artifact of NGO exaggeration of the threat.  But I hasten to add that I don't follow the investment cases closely, so perhaps someone would point me to some smoking gun cases.