Sometimes the Jacketing process sets different NURBS faces to B-sides depending on the given scale factor of the geometry (e.g. Scale = 1.0 compared to Scale = 0.1).
This is a known limitation of the Jacketing algorithm along with the used shrink-wrap-mesh calculation. During the Jacketing process the shrink-wrap-mesh moves close to the wrapped objects surface and trys to stop when the geometry and the mesh start to touch each other. This process is only as good as the resolution of the shrink-wrap-mesh in relation to the complexity of the wrapped object(s).
To influence the result you can either avoid scaling the object after the inital Jacketing calculation or adjust the resolution of the shrink-wrap-mesh to compensate for any changes. In general it is a good idea to use the Jacketing function at the end of the data manipulation process and to run it only once per Jacketing group.