I'm curious, why do we have it the way we currently do? Seems to me that the mainline of E-470 takes they bypass, and doesn't take the highway ramps down to the surface streets to access I-70 @ Exit 289. It used to go thru the I-70 interchange, but was bypassed back around 2006 (per Wikipedia).
To me, I think there should be 3 points there for E470 and 2 points for I-70.
E470:
20A http://www.openstreetmap.org/?lat=39.733033&lon=-104.717265
20 http://www.openstreetmap.org/?lat=39.740203&lon=-104.718745
20B http://www.openstreetmap.org/?lat=39.746423&lon=-104.716820
And reuse the '20' line and put it into I-70 (US-36/40/287)'s file as either E470 or 289A, and leave the current 289 alone.
I know that the 'lettering' is off some for E470, since what I have as 20 above is really 20B, but I thought that would be the best solution in this case to not break list files too badly and keep everybody defaulted to I-70's point. People can later adjust to exactly which ramp they used to correctly mark their travels.
This way, they still maintain the graph connection, but it's at least accurate now. Plus each point on E470 is right around 0.5 miles apart.
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On a side note, there's a new exit on E470 as well. It's where the old toll booths were going NB (only a NB exit at this time). It might shift locations to the new East 38th Avenue overpass that's under-construction, but I don't know for sure.
22
https://goo.gl/maps/puaf1SRbippVjFQV7