I don't understand.  This is where you seem to be claiming all slip roads should be link, but admit that some cannot be.  Hence my suggestion above that after the previous discussion you've seen that not all slip roads can/should be link.  Is this not the case?

To be completely clear, can I just check with you that you've seen that the A516 runs from the Derby inner ring road to the A50 N of Hilton, and the only part that is not the A516 is where the A38 ref takes precedence.  The roundabout outside the Royal Derby Hospital is not the termination and the A516 does not run along the (now tertiary) Uttoxeter Road any more.  The change from OSM primary to OSM trunk at the roundabout is probably because of the newer road design/build standard not because an A38 connection exists; the A516 (OSM) trunk continues to N of Hilton.

In the absence of roads linking between A roads or terminating to/from lower types, I do not see that the trunk_link page description has any relevance.  The wiki description of trunk roads says highway=trunk.  Does this trunk status (which I regard as higher status) not 'win' over OSM's provision of a trunk_link concept to mark roads which connect to/from such ways and generally have no ref or name themselves.

I'm trying the keep the map correct, not to disturb your editting.