Store influence weights of skinClusters per vertex per joint in 3D space. This point-cloud based method can be abstracted to save spatial data to a file and reimport it back to apply to the same or other skinClusters. This allows for saving good skin-data externally, skin clusters can be removed and the mesh or skeleton can be adapted freely before importing the weight cloud again.
The joint bindings are name based as opposed to dag paths, allowing for different rigs on the same skeletal structure. It is of course also possible to create stub joints to later remove. The weight cloud can be applied to vertex numbers, but it can als obe sampled freely. This way weights can be transferred freely between similar meshes - or not so similar meshes.
There are many ways to use this one feature fairly extensively. As long as we're not talking extremely thin faces there is a very wide diversity of applications and techniques. Having skinned one mesh it is possible to export the weights, detach the skin and modify the mesh shape. Then it is possible to rebind the skeleton and reimport the same weights by vertex number. Next step can be to export those weights again to a weightcloud and import them onto another mesh, not by vertex number but spatially this time. This allows for one skinned mesh to be quickly deformed to match another and to transfer those weights unto that mesh more accurately.
It may also not be unwise to smooth the mesh before skinning it if it is intended to be transposed to other meshes, as the pointcloud will have more accuracy.