I'm with you now, IO540.
Originally, I had missed the significance of the "P" in the P-RNav in your original post, but it clicked as I was writing my reply, and I now see exactly where you're coming from.
I think P-RNav is likely to become more and more common, though, with more RNav approaches popping up all over the place, and ICAO wanting to have an RNav approach on every instrument runway within a few years (I think 2018 was the target?).
But the aircraft I fly are all P-RNav-approved, it's easy for me to talk about a P-RNav world and forget the very valid point you make about the cost of the approval.
FFF
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