Sillypeoples:
Well I think some guys get caught up in the terminology...we all know what a technical overlay is...technically they are the same approach with both approaches depicted.
Nope, when the U.S. had overlays there was only one chart.
In this case, it's just obvious that the GPS approach was built off of the VOR approach, being a straight in, they had to line up for a straight in, vs what is best for a circling approach. Given that both approaches have only a difference in inbound headings of ten degrees, its a given for me that if your on the GPS approach and lose the box at say 4k, why not have the inbound VOR radial dialed in as a back, for better situational awareness, as another way to depicts the MAP, then simply side step to the 293 inbound to 2880.
The RNAV IAPs were designed from a clean sheet, with all the technical stuff that goes with LPV and LNAV/VNAV.
The FAA premise is that there is so much airspace in a conventional RNAV IAP that the pilot can dead reckon the missed approach in that very unlikely event.
But, not so with RNP AR unless it is basic RNP 0.30 with a conventional TERPS missed approach. Otherwise, you have to have at least one IRU for extraction in that very unlikely event GPS is lost. RNP AR approaches with RNP missed approach procedures "telescope" in width in accordance with IRU drift rate assumptions.
Using GGW as an example that VOR will be shut down as time goes on.