Long time ago (Blender 1.80 I think), it was possible to save a vertex group and after subdivision from the vertex specials menu, the newly created vertices weren’t added to the group.
Recent versions of blender, however, add the new vertices to the group. Is there a way how I could store the vertices before subdivision and select them afterwards?
yes, but it took quite a bit of brainpower to think this one up. You would think that, before subdivision, select all vertices and create a new vertex group, and Assign them. Do your subdivision on all or some of them. Select none. In the Vertex Group panel, click Select. Only the original vertices will be selected. WELL NOOOOOOOO… you are correct, SO
Create a mesh, create a group. Duplicate the mesh and do not move it. Subdivide it. Join the two objects the duplicated one to the parent, and remove doubles. Select the group and voila. only the originals remain selected. i think order of joining is important so that when dupes are removed, the originals that are part of the original group remain.
Good question. njoy.