All States accept the placing of performance within the Limitations (or within section 1 of the manual). This is only an issue with regard to the limitation of the HV Diagram when the aircraft is operated outside of a Category A procedure.
The probability of having a Category A procedure for offshore operations is vanishingly small (for the reasons stated in my previous post). The very nature of helidecks therefore means that during take-off and landing there will be an incursion into the HV diagram (just think it through). The requirement to apply the limitations of the RFM is (almost always) placed in the basic regulations of the State. If the HV diagram is within the limitations section, the pilot will be in contravention of this limitation. This means that, for those States who understand and recognise the issues of offshore operations, an alleviation must be provided to avoid deliberate breaching of the regulations.
The FAA avoids this situation by alleviating from this limitation in FAR 91.9(d) - but only for operations over water. The JAA copied this alleviation into JAR-OPS; during the transposition of JARs to EASA OPS, this was removed - which left all offshore pilots in deliberate breach. After a convoluted discussion where unrealistic alternatives (amendment of Part 29) were proposed, EASA amended the basic regulation to contain an alleviation. similar to that previously written. The difference now is that the FAA only allow this over water but EASA allow it universally (in accordance with the Code of Performance). In addition, the FAA, recognising the difficulties of offshore offshore operations have OpsSpec H 100.
In the paper it is rightly stated that formerly, Category A helicopters were certificated with only the clear area procedure (runway-type). At the time that FAR 29 was written, it was thought that helicopter would only be operated from airfields (the same was true of ICAO Annexes 6, 8 and 14). That this was not true was accepted and FAR 29 was amended as part of NPA 80-25. Realistically, Part 29 has not changed in substance since then. The changes made to Part 29.1 presaged the introduction of the Performance Classes - as the paper stated, Category A, Category B and a hybrid (Performance Class 2).
Even though NPA 80-25 recognised that operations to other than runways would become the norm in the future, the nature of that change was not apparent. Chapter 2 provides a framework for Category A procedures that is completely objective and has no knowledge of the use to which it will be put. Procedures could be provided to suit any operational requirement; it provides a facility for provision of procedures not a compulsion - i.e. a capability. The manufacturer provides a suite of Category A procedures; if required by the Code of Performance, the operator uses one of these procedures and adapts it to the obstacle environment.
In fact, procedures are split into two types: the runway-type - the clear area procedure (very similar to fixed wing); or vertical procedures - where the profile requires a vertical component - i.e. the ascent to the TDP or the descent from the LDP. This vertical component allows the building of potential energy (the height of the TDP) that can be converted to kinetic energy (speed of the helicopter) whilst accelerating over obstacles to reach a speed that permits a safe climb. It is this unique capability of the helicopter (including eVTOL) that allows operations from small heliports (ground level or elevated) in virtually any obstacle environment.
To return to offshore operations: a Category A procedure meeting all of the clauses of Part 29, Chapter 2 and suiting the helideck environmental conditions set out previously would required the power of a Wessex (which could take-off, fly, and land on one engine). The helideck environment has neither the facilities of a runway nor the ability to apply vertical procedures that permit the helicopter to achieve engine failure accountability at reasonable operating masses. It is, and will remain, an outrider that has to be addressed with realistic solutions.