Strange mesh behavior with proportional edit I have a simple mesh which behaves like it has a "rip" when using proportional edit.

This mesh has no vertex groups, constraints, modifiers, but moving a vertex with proportional editing highlights the problem - not all vertices "follow their orders". Only each separate half of the mesh reacts to proportional edit independently, depending on initial selection.

When I isolate this mesh to another file, the problem comes along with it. Here is the file https://www.dropbox.com/s/bc4etnzfg7knwg0/OddMesh.blend?dl=0
LukeD was right, following his tips the "rip" seemed to happen along the local Y axis of the object, moving the mesh in Edit Mode along the X axis so it would no longer overlap the Y=0 axis, would alleviate the problem.

The problem it seems is the Mirror X option that was active in the object editing options. In the 3D View Tools shelf > Options Tab > Mesh Options disable X Mirror option.



There did seem to be some sort of symmetry in the works, I searched for the setting but could not find it anywhere myself, this video however helped shed some light on the issue.