Lizard,
I don't believe the RMI needle can point to an RNav point on most kit?
That aside, setting the RNav point and then flying a published NDB hold based on RNav-derived tracking information sounds, to me, no more legal (but just as safe) as flying an NDB approach based on RNav-derived tracking information.
As for holding prior to an RNav approach, holding at the IAF seems entirely logical to me too. I heard a rumour recently (but I can't for the life of me remember where) that Exeter ATC are introducing informal procedures to do exactly this for locally-based aircraft, although if they are informal procedures I'm sure they wouldn't be appropriate for an IR test.
I've seen draft plates for the Alderney RNav procedures which featured a hold to the north of the airport, based on an RNav point. I have no idea how "draft" these plates were, or whether this hold will make it into the final procedure when it's eventually published - but it does show that offical, published holds away from beacons are feasible and are being considered.
FFF
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