While trying (and failing) for the 30th time to come up with a Raleigh-Durham rail alignment that both hits the RDU terminals and doesn’t suck in every other possible way, I did come to realize that a world-class HSR line for the North Carolina Piedmont Crescent is actually not as hard as you might think.
By combining together some segments of the existing RR, power line easements, highway rights-of-way, and a few rural greenfield segments, you can get a HSR line that could go from Raleigh to Greensboro in something between 30-40 minutes.
With the exception of 6 miles through central Durham and 5 miles through central Burlington where the speed limit would probably be under 100mph, the speed limit could easily be 200mph for the rest of it.
There are a couple of tricky transitions that would have to be worked out. The worst one is getting from Wade Avenue to the NCRR through the NCSU vet school. Another one is just west of Burlington. Another one that would probably not be controversial but would be kind of expensive would be that the ROW would require acquiring and demolishing the Hilton Garden Inn at I-40/Miami Blvd.
Interestingly, There would have to be a short tunnel punching right through the center of Occoneechee mountain in Hillsborough.
(Tacked on part of the proposed SEHSR alignment from Raleigh to Wake Forest just for kicks.)