Huh, so NCDOT plans on adding two-more double-3di concurrencies to the system (785/840 and 587/795) in addition to Ohio's 271/480 concurrency.
Yep. It's the only way I-785 and I-795 can connect with their parents.
I suppose for 785 they could upgrade things in Greensboro and route 785 directly down 29 and Business 85.
If I'm not mistaken, I believe that was the original plan in the 1990's (I-85 was concurrent with I-40 then) but that changed when upgrading US-29 through Greensboro to interstate standards was deemed not feasible due to the expense and impact of such an upgrade. So, the decision was made to throw I-785 onto the Greensboro Urban Loop instead.