Meshes: how can I hide polygon edge lines between adjacent co-planar faces only, showing the rest

[Paul King]

I need a way for meshes to hide triangulation lines in plan where adjacent faces of mesh are coplanar, but to still show lines corresponding to actual ridges.

For example, if I cut a notch in the edge of a mesh, even though the slope of the mesh is unchanged around the notch, useless extra lines in plan appear to triangulate the mesh around the notch.

These extra lines communicate nothing meaningful to the builder, and in fact create confusion because they have no physical or geometric meaning on site. 

I do still need actual changes in plane to be represented in plan - because those lines do have a physical/geometric meaning.

How do people accomplish clean looking meshes in plan that deal with situations like this, without resorting to 2D fudges that multiply the work required in every affected view and the risks of error every time the mesh is moved or edited?

The 3D appearance options seem to be no help here.

I tried converting mesh to morph as a last resort (I really don't want morphs as will need ability to edit again in future) , and trying 'smooth and merge faces' and 'smooth and merge edges' seems to give no improvement - the boundary lines between adjacent coplanar triangle polygons remains. 

Noting I don't want to smooth away ridge lines where adjacent polygons have slightly different planar inclinations

[Barry Kelly]

You can't pick and choose which mesh line you can or can't show.

You can choose to show just the user defined ridges (contours) and not the triangulation.

With a morph, you can select the individual edges and hide them.

Barry.