...don't forget the alleviations from the HV curve contained in FAR 91.9(c) and Appendix 1 to JAR-OPS 3.005(c).
Attempting to regulate operations from inside Part 29 was always an unrealistic proposition. This has been recognised for some time but still results in a head-in-the-sand attitude by some regulators. (Explain to me how offshore operations can be conducted in the GOM without breaching this limitation - not just for the helicopters mentioned but also for the S92 and EC225.)
Fortunately there is a move by EASA to resolve this (at least for Europe); they have it on their work programme to be addressed before EASA OPS comes into effect.
The masses have changed in recent years - the break between Part 27 and 27 is now 7,000lbs not 6,000lbs.
Jim