That seems like cherry picking the offenders to invalidate the entire class of vehicles.
…Porsche hybrids consumed more fuel – around seven litres per 100km – than other PHEVs when the electric motor kicks in, and significantly more than non-PHEVs in combustion engine mode. The lowest fuel consumption levels were found in the cheaper end of the PHEV market, in Kia, Toyota, Ford and Renault vehicles, which often used under one litre per 100km, or as much as 85% less fuel than the Porsche.
If I am buying a PHEV, I am not getting a Porsche or BMW.
On the other hand, if I'm in the market for a Porsche or BMW commuter, the cost of fuel is basically negligible and a PHEV for performance or convenience or comfort would influence my decision far more than a relatively insignificant amount of fuel savings.
