kentsmith9 wrote:I don't think "junction at one end must have a freeway/highway/ramp segment" is true based on my knowledge.
Unless someone can identify the problem (which then can be added to the Wiki), it is certainly possible for one (Primary) Street to pass over another (Primary) Street and have a connector between them marked as a Ramp. In that situation a Ramp is fully legitimate, but not required.
Kent, I think the vast majority of situations will have a ramp connecting to a mH, MH or Fwy. However, you are correct, and I have these in my area, where primary streets cross over and there are ramps used to connect them. I believe these are legitimate use of ramps as well. "Grade-separated" doesn't exclude Primary Street type.